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Archaeology in Eastern Africa: Recent Developments and More Dates Peter Robertshaw The Journal of African History / Volume 25 / Issue 04 / October 1984, pp 369 393 DOI: 10.1017/S0021853700028449, Published online: 22 January 2009
Link to this article: http://journals.cambridge.org/abstract_S0021853700028449 How to cite this article: Peter Robertshaw (1984). Archaeology in Eastern Africa: Recent Developments and More Dates. The Journal of African History, 25, pp 369393 doi:10.1017/ S0021853700028449 Request Permissions : Click here
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Journal of African History, 25 (1984), pp. 369-393 Printed in Great Britain
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ARCHAEOLOGY IN EASTERN AFRICA: RECENT DEVELOPMENTS AND MORE DATES1 BY PETER ROBERTSHAW T H I S is a further article in the Journal's series of reviews of recent archaeological research and radiocarbon dates for Eastern Africa.2 In geographical scope and format the present paper follows that of Mgomezulu fairly closely.3 A regional presentation of recent archaeological work, irrespective of whether or not it has resulted in new radiocarbon dates, is presented. Coverage of the various regions is not necessarily uniform and I make no claim that it is comprehensive. Like previous authors of articles in this series, I have been dependent upon the co-operation and kindness of numerous researchers, who have made information available to me often in advance of their own publications. Radiocarbon dates not published previously in this journal are listed in the Appendix by country and site. All dates are from archaeological sites; I have not listed dates of palaeoenvironmental significance, though some of these are referred to in the text. I have followed the usual convention of employing the 5,568-year half-life with the dates adjusted4 to a.d. and b.c. by the subtraction from or of 1,950 years. In the text I refer to dates only by broad periods approximating to their standard deviations. Before going into regional and chronological detail, some of the salient methodological developments and prominent results might be outlined. On the Eastern African scene, attention has been devoted in recent years to the development of dating by obsidian hydration. Important work has also commenced on the chemical sourcing of obsidian artefacts as a basis for the elucidation of prehistoric exchange networks. Some critical evaluation of radiocarbon dates used as evidence for very early domestic animals and crops has been attempted. These developments, which are outlined below, have gone hand-in-hand with new field research. In the Southern Sudan investigations have commenced at several of the numerous mound sites found in areas today occupied by Nilotic-speaking pastoralists. At one of these sites, beside the Nile in Er Renk District, charcoal apparently associated with iron objects has been dated to early in the first millennium b.c. Further south, in the Turkana District of Kenya, a new survey of the Namoratunga II site has led to a challenge to claims that it is an archaeo-astronomical site. Recent fieldwork has perhaps failed to clarify the dating and associations of both the Turkwel Tradition and the Namora1 I wish to thank all those people who made this review possible by their generosity in providing information. Many researchers went to considerable trouble to educate me about their work and provided offprints. I am also grateful to Gadi Mgomezulu, who gave me the benefit of his own experience in preparing this type of article. Harry Merrick and John Sutton made many helpful comments on an earlier draft. 2 The previous two reviews of Eastern Africa for this journal were prepared by T. Maggs (XVIII, ii, 1977) and G. G. Y. Mgomezulu (xxn, iv, 1981). These articles are referred to below simply by the author's name and relevant page number. 3 4 Mgomezulu, 435. N.B. Not corrected.
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tunga cemeteries, though casting these problems in a new light. Prehistoric investigations in the interior of Somalia have been resuscitated by Steven Brandt, and new dates pertaining both to the appearance of food production and to earlier periods have already been obtained. By contrast, research on the later prehistory of Ethiopia appears to have been minimal in recent years, though some new information is available from the Lake Besaka area. In the Eastern Province of Kenya, several of the elaborate stone cairns which dot this region and demonstrate cultural ties with the Horn have been excavated and their contents dated. Rock-shelters in the central Rift Valley of Kenya and shell middens beside Lake Victoria, both occupied by hunter-gatherers in the early and midHolocene, have been excavated; these are refining our knowledge of changing subsistence practices and our understanding of what has been called the 'aquatic civilization of Middle Africa'.5 Excavations have been carried out at Mumba-Hohle and Nasera Rock in northern Tanzania which are especially important for our understanding of the beginnings of the Later Stone Age. Considerable new information on the Elmenteitan and other traditions generally termed' Pastoral Neolithic' has accrued from survey and excavations around Lemek in south-western Kenya and from detailed laboratory studies of faunal assemblages from several sites, Prolonged Drift in particular. A number of dates have become available for excavated Early Iron Age sites in Kenya, though none is yet available for well-preserved furnaces found in the Taita Hills. For the later Iron Age, several new dates in the mid-late second millennium a.d. from Engaruka further undermine any suggestion of a first millennium a.d. occupation at that site. At the coast, excavations at Shanga and Pate, together with work at Manda summarized previously,6 have illuminated the beginnings of settlement beside the sea and by implication the origins of the Swahili. The first fledgling attempts have also been made to consider quantitatively patterns of settlement over broad regions of the East African coast. Recent research in Zambia and Malawi continues to improve our knowledge of Iron Age ceramic traditions and subsistence, and also of probable interaction between farmers and hunter-gatherers. In Malawi the history and technology of iron-smelting is being investigated by archaeological, historical and experimental work. Dating problems and prospects
In his recent review of West African archaeological research, Sutton drew attention to some of the abuses commonly perpetrated by both historians and archaeologists in writing about radiocarbon dates.7 However, we must not throw out the baby with the bathwater by considering radiocarbon dating as some elaborate guessing game in which the application of corrections is an accepted form of cheating. Great progress has been made in recent years in the refinement of radiocarbon dating, particularly of very small samples of organic materials. Of especial interest and importance for historians concerned 6
J. E. G. Sutton, 'The aquatic civilization of Middle Africa', J. Afr. Hist, xv, iv 8 (1974), 527-46. Mgomezulu, 448. ' J. E. G. Sutton, 'Archaeology in West Africa: a review of recent work and a further list of radiocarbon dates', J. Afr. Hist, xxin, iii (1982), 291-313.
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with the Iron Age is the new high-precision calibration curve for the last 2,000 years,8 which can be used for a large part of the northern hemisphere and probably the southern hemisphere as well.9 However, these advances do not relieve archaeologists and historians of the obligation to evaluate carefully the context of the material dated and the strength of the association between the charcoal sample10 and the archaeological finds which it purports to date. One problem, which seems particularly to afflict archaeologists investigating sites of early pastoral communities in Eastern Africa, is that often no charcoal is recovered from excavations. When this happens, bone is often used for dating. Radiocarbon readings can be obtained from both the collagen and apatite fractions of the same sample of bone.11 However, it often happens that the results from the two fractions are not in statistical agreement; it seems that many bone dates should be regarded as unreliable.12 Because of this problem, the claims that have been made for very early domestic stock in East Africa,13 which are based on bone apatite datings, should be held in abeyance until better substantiation is available.14 The earliest securely dated evidence to hand for domestic stock in Kenya puts their appearance around the beginning of the second millennium b.c.15 In parts of Eastern Africa archaeologists are fortunate that most prehistoric stone tools were made from obsidian, a natural volcanic glass. It is possible to date obsidian artefacts directly.16 Also, since sources of obsidian are relatively few, it may be feasible to 'fingerprint' particular artefacts to specific sources. Archaeologists have only recently begun to seize the opportunities of dating and sourcing. Michels and his associates have established specific hydration rates for several compositional types of obsidian found at archaeological sites in Kenya. This has allowed them to date artefacts from several sites, including more than fifty artefacts from Prospect Farm spanning about 120,000 years.17 Michels18 also reports that he has successfully dated Middle Stone Age artefacts from Pore Epic Cave and Acheulean 8
M. Stuiver, 'A high-precision calibration of the A.D. radiocarbon time scale',
Radiocarbon, xxiv, i (1982), 1-26. 8 Stuiver, ibid. 5, remarks that 'systematic radiocarbon age differences for southern hemispheric samples still have to be tested in more detail'. 10 Or whatever the substance is that is dated. 11 The results should be corrected for the fractionation of the stable isotope C13. The measurement of stable isotopes has very considerable potential for the study of prehistoric diet and palaeoenvironments; see, for example, N. J. van der Merwe and J. C. Vogel, 'Recent carbon isotope research and its implications for African archaeology', African Archaeological Review, 1 (1983), 33-56. 12 A statistical analysis of bone dates from East Africa is to be found in David Collett and Peter Robertshaw, 'Problems in the interpretation of radiocarbon dates: the Pastoral Neolithic of East Africa', African Archaeological Review, I (1983), 57-74. 13 See Mgomezulu, 441. 14 Collett and Robertshaw, 'Problems'. 16 Ibid.; see also R. B. Owen, J. W. Barthelme, R. W. Renautand A. Vincens, 'Palaeolimnology and archaeology of Holocene deposits north-east of Lake Turkana, Kenya', Nature, ccxcvm (1982), 523-9. 16 Using the obsidian hydration method; see, for example, J. W. Michels, Dating methods in archaeology (New York, 1973), 201-18. 17 J. W. Michels, I. S. T. Tsong and C. M. Nelson, 'Obsidian dating and East African Archaeology', Science, ccxix (1983), 361-6. 18 Personal communication. 13-2
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handaxes from the Gadeb site, both in Ethiopia.19 Obsidian sourcing is being pursued by Brown and Merrick.20 They have succeeded in characterizing chemically many obsidian sources in the Central Rift region of Kenya and have begun matching artefacts to these sources. Their preliminary results indicate long-distance movement of considerable quantities of Central Rift obsidian from Middle Stone Age times onward over southern Kenya and northern Tanzania. It also seems that the makers of different early pastoral ceramic traditions may have generally used obsidian from different sources.21 The Research Laboratory for Archaeology at Oxford is attempting to develop a new dating technique for Eastern African sites.22 The aim is to establish a reference curve of variations through time in the direction and intensity of the earth's magnetic field. This is done by examining small cores of fired ceramic material from well-dated archaeological contexts. However, most ceramic samples so far analysed from Eastern Africa have failed to meet strict criteria applied to test their magnetic reliability. Therefore it seems that as yet there is little hope of developing a curve for this region to be used as a dating tool. THE HORN OF AFRICA23 Results are now available from excavations undertaken in the mid-1970s at several sites near Lake Besaka in Central Ethiopia.24 Occupation of the area began in the late Upper Pleistocene about 22,000 years ago and continued to about the mid-second millennium b.c. Five temporal phases have been recognized, which form a single technological tradition known as the Ethiopian Blade Tool Tradition. The Later Pleistocene Phase, which dates to between about 10,000 and 17,000 b.c. (UW-492, UW-493, UW-494, UW-495), represents the earliest well-documented evidence in the Horn for a microlithic Later Stone Age industry, during what seems to have been a more humid period than the present. A scraper-dominated Earliest Holocene Phase is succeeded by the Metahara Phase of the Besaka Industry dating from early to mid-Holocene (SUA-469A, SUA-469B, SUA-470, UCR-483).25 This Phase, containing large numbers of geometric microliths, is notable for evidence of extensive exploitation of aquatic resources at a time when Lake 19
It should be noted that not only can obsidian hydration dating be applied to a greater timescale than radiocarbon, but also it is a considerably cheaper analytic process. Michels operates a commercial obsidian dating service named MOHLAB. 20 Pers. comm. I am grateful for information supplied by H. V. Merrick. 21 Merrick, pers. comm. 22 G. Bussell, pers. comm., kindly provided the information set out in this paragraph. 23 I am especially grateful to Steven A. Brandt for his generosity in making the results of his research available to me. Without his assistance this section of the review would not have been possible. 24 S. A. Brandt, 'A late Quaternary cultural/environmental sequence from Lake Besaka, Southern Afar, Ethiopia' (Ph.D. thesis, University of California, Berkeley, 1982); idem, 'Archaeological investigations at Lake Besaka, Ethiopia', in R. E. Leakey and B. A. Ogot (eds.), Proceedings of the Eighth Panafrican Congress of Prehistory and Quaternary Studies (Nairobi, 1980), 239-43; J-D. Clark and M. A. J. Williams, 'Recent archaeological research in southeastern Ethiopia (1974-75): some preliminary results', Annales d'Ethiopie, xi (1977), 19-42; M. A. J. Williams, P. M. Bishop, F. M. Dakin and R. Gillespie, 'Late Quaternary lake levels in southern Afar and the adjacent Ethiopian Rift', Nature, CCLXVII (1977), 330-2. 25 All these dates are not C13-corrected and all are therefore considered to be minimum age estimates; see Brandt, thesis.
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Besaka had greatly expanded in size. Pottery and grindstones make their first appearance in the Abadir Phase of the Besaka Industry dating to around the beginning of the third millennium b.c. (I-8330).26 Faunal remains from this Phase include a wide spectrum of bovids and other large mammals as well as large amounts of fish remains; however, no domestic animals are represented. By the beginning of the second millennium B.C. the climate in the region had become semi-arid; fish remains are absent from the Late Holocene Phase dating to the mid-second millennium b.c. (1-7969). A few teeth from Fejx3, a Late Holocene Phase site, have been tentatively identified as those of domestic cattle. Test excavations by Brandt and Gresham in two limestone caves in northern Somalia have revealed evidence of Upper Pleistocene occupation.27 Two dates (UW-787, UW-761) are available from the site of Medishe 2, which contains a sequence of Middle and Later Stone Age horizons, while one date (UW-762) of greater than 40,000 years comes from Gud-Gud. The site of Karin Hagin contains numerous monochrome and polychrome paintings, mostly of long-horned humpless cattle. Probable goats, at least one dromedary camel, and a variety of other motifs including human figures are also represented. Excavation in the floor of the shelter revealed a microlithic assemblage with rare potsherds, which has been dated to roughly the early part of the first millennium a.d. (UW-763, UW-764). The excavators comment that, given our present lack of knowledge of the origins of domesticated camels in the Horn, the apparent contemporaneity of the camel illustration with humpless cattle, presumed to be of Neolithic age, is a matter of considerable interest. Brandt is now excavating further south in the rock-shelter known as Gogoshees Qabe in the Buur Heybe inselberg.28 Graziosi excavated a small trench at this site in 1935 to a depth of 4 m without reaching bedrock.29 So far, Brandt has excavated 30 m2 to a depth of 1 m. The lower levels of his excavations contain a Later Stone Age assemblage associated with an exclusively wild fauna and six complete human skeletons, while the upper levels have stone tools, pottery, and faunal remains which include rare domesticated cattle and sheep/goat. Four complete human skeletons were also recovered from the upper levels of the site, which has now yielded the largest prehistoric Homo sapiens skeletal population from the Horn of Africa. No date is yet available. THE SOUTHERN SUDAN
Recent archaeological work in the Southern Sudan has been concerned almost entirely with the investigation of mound sites of the sort generally known as debbas, which are found throughout the seasonally flooded grasslands surrounding the Sudd swamps. Excavations are revealing a complex culture26
Four other dates from the same site (UCR-482, SUA-468A, SUA-468B, UCR-481) are not C13-corrected and are considered to be minimum age estimates; see Brandt, thesis. 27 S. A. Brandt, G. A. Brook and T. H. Gresham, 'Quaternary palaeoenvironments and prehistoric human occupation of northern Somalia', Proceedings of the Second International Congress of Somali Studies (Hamburg, in press). 88 S. A. Brandt, pers. comm. 28 P. Graziosi, L'Eta della pietra in Somalia (Florence, 1940). This site was referred to as Gure Makeke in J. D. Clark, Prehistoric cultures of the Horn of Africa (Cambridge, 1954). I thank Dr Brandt for this information.
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30°
10°-
30°
35°
40°
45°
50°
Figure i. Horn of Africa, Northern Kenya and Southern Sudan 1. 2. 3. 4. 5.
Lake Besaka Medishe 2 Karin Hagin Gud-Gud Gogoshees Qabe
6. 7. 8. 9. 10.
Debbat El Eheima Debbat Bangdit Kat, Bekjiu, Na'am Jokpel, Ngeni A and B Kalokol
11. 12. 13. 14. 15.
Lokori Kampi ya Samaki Fwjh 16 Kokurmatakore North Horr
historic sequence spanning the last three thousand years which should add considerable detail to our understanding of human settlement in this inhospitable region. The debbas found on the Dinka and Shilluk Ridges in Upper Nile Province have been investigated by Kleppe.30 Two sites have been excavated, and a third tested.31 Numerous potsherds, as yet undescribed, and occasional stone artefacts were found throughout the 2 m depth of deposit at Debbat El Eheima, the bottom of which dates to around the end of the second millennium b.c. (T-4811, T-5032). Other finds include two graves covered by a layer, 25 cm thick, of large potsherds, as well as numerous beads, bracelets and pendants in various raw materials. In addition, of great interest was the discovery of fragments of forty iron objects, most of which came from the top 90 cm of deposit. A charcoal sample from the 60-70 cm level, apparently in good association with several small iron points, has provided a date around the ninth or eighth century b.c. (T-4562). This date is two to 30
For an introduction to her work see E. J. Kleppe, 'The Debbas on the White Nile, Southern Sudan', in J. Mack and P. Robertshaw (eds.), Culture history in the Southern Sudan (Nairobi, 1982), 59-70. 31 E. J. Kleppe, 'Towards a prehistory of the riverain Nilotic Sudan: archaeological excavations in the Er Renk District', Nubian Letters 1 (1983), 14-20. Dr Kleppe, whom I thank for providing me with details of several unpublished dates, reports that a monograph on her research is in preparation.
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three centuries earlier than the earliest evidence for iron-working at Meroe about 600 km to the north;32 confirmation is clearly required through the dating of further samples and publication of full details of the context of the charcoal samples and the iron objects. A similar range of archaeological material was found within the 2 m or more of deposit at Debbat Bangdit.33 No description of the pottery is yet available. Five graves were found, all of which were covered with thick layers of potsherds. The majority of the dates fall roughly in the mid to late first millennium a.d. (T-5063, 4, 5, 7, 8), with one date from the upper levels of the mid-second millennium a.d. (T-5066). Six mound sites have been excavated on the edge of the seasonally flooded grasslands close to the ironstone rim in Lakes Province to the south-west of the Sudd.34 What is probably the earliest material comes from the lower levels of the site of Kat, though no date is yet available, where pottery was found which is decorated generally by comb-impressions often applied in a rocked zigzag motif. The upper levels at Kat are ash deposits, probably resulting from the use of the site as a cattle-camp. The pottery from these levels is very similar to that presently used in the area by Dinka Agar. There are two 'modern' dates for the upper levels (Hel-1553, Hel-1554). Further east, at Jokpel, the lowest horizons contain thin-walled, undecorated potsherds belonging to open bowls; associated finds include a clay figurine of a humpless cow. These deposits are overlain by about a metre of sandy loam towards the top of which were found a series of burnt clay floors. The pottery is characterized by the application of all-over woven mat impressions. Though undated at Jokpel, the same pottery tradition is represented throughout the large site of Bekjiu, where six dates span the period from about the sixth to twelfth centuries a.d. (Hel-1547, 1548, 1549, 1555, 1556, 1557). Iron objects were also found. The faunal remains include numerous domestic animals and fish bones. The nature of the deposits suggests that this site may have been originally used as a cattle-camp. However, at about 60 cm depth there is evidence of more permanent structures with hardened clay floors and wall plaster, though the final use of the site appears again to have been as a cattle-camp. Such a sequence of different uses of the site is reflected in oral traditions collected in the area.35 The extended skeleton of an adult male in which the incisors were present was excavated from the bottom of one of the trenches at Bekjiu. Two further sites (Ngeni A and Ngeni B) with pottery like that of Bekjiu were tested but no date is available. Finally, at the site of Na'am archaeological deposits reached a depth of 2 m. Much of the pottery from this site is comparable to modern Dinka pottery. Three dates, the lowest from 150 m below surface, are all 'modern' (Hel-1550, 1551, 1552). The associated faunal remains include domestic cattle and a wide variety of fish and fowl. From the results of excavations at all the sites combined it seems 32
P. L. Shinnie and F. J. Kense, 'Meroitic iron working'. In N. B. Millet and A. L. Kelley (eds.), Meroitic Studies: proceedings of the Third International Meroitic Conference, Toronto 1977; Meroitica vi (1982), 17-28. 33 Kleppe, 'Towards', and pers. comm. 34 Information on sites investigated in Lakes Province can be found in P. Robertshaw, A. Siiriainen, A. Tor, B. Mbae, T. Andersen, J. Coote and A. Mawson, 'Expedition to the Southern Sudan of the British Institute in Eastern Africa', N'yante Akuma xvm (1981), 48-50; P. Robertshaw and A. Siiriainen, in preparation. 36 J. P. R. Coote, in preparation.
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that the appearance of modern Dinka pottery perhaps correlates with a change in the use of the mounds to cattle-camps from what may have been more permanent villages. A switch to a dispersed pattern of permanent homesteads in contrast to earlier, large villages such as Bekjiu may also have occurred at this time. This in turn might possibly be linked to the arrival of the present inhabitants of the region within the last few centuries. NORTHERN KENYA
While not resulting in any new dates,36 recent fieldwork has considerable implications for our understanding of the Namoratunga archaeo-astronomical and cemetery sites.37 Soper recently resurveyed the supposed astronomical site at Kalokol and his results suggest that there are serious errors in Lynch's survey.38 Therefore Soper rejects the hypothesis of an astronomical function for the Kalokol site, at least in the form presented by Lynch and Robbins with a specific Eastern Cushitic parallel.39 Soper also points out that since the direction of rising of the stars/constellations is not significant, markers like the Kalokol stones would have no practical function in the Eastern Cushitic calendar.40 The supposed contemporaneity of the Kalokol and Lokori sites is also questioned, as are several points of detail concerning the interpretation of the Lokori site.41 Following directly upon Soper's article in Azania there is a reply by Lynch published posthumously; readers of this journal are encouraged to read and judge for themselves this interesting dialogue. Further new information relevant to this discussion is the discovery of a burial complex, very similar to that of Lokori, at Kampi ya Samaki beside Lake Baringo.42 Unfortunately no date is yet available for this site, which also appears not to have any rock engravings. From the same area as the Namoratunga sites, Lynch and Robbins found grooved pottery which they named the Turkwel Tradition and linked to Eastern Nilotic speakers.43 A recent review of the dating evidence for this tradition argued that only one date, of around the eleventh century a.d., could be given any credence.44 However, a site (Fwjhi6) with Turkwel pottery recently tested by Soper has yielded a surprisingly early date in the mid second millennium b.c. (GX-9747).45 While more dates are required, the 36 Readers are referred to Collett and Robertshaw, 'Problems', for a critical review of already published dates for northern Kenya. 37 For the original descriptions of these sites see B. M. Lynch, 'The Namoratunga cemetery and rock art sites of N. W. Kenya: a study of early pastoral social organisation' (Ph.D. thesis, Michigan State University, 1078);!$. M. Lynch and L. Robbins,'Namoratunga: the first archaeo-astronomical evidence in sub-Saharan Africa', Science, cc (1978), 766-8; B. M. Lynch and L. Robbins,' Cushitic and Nilotic prehistory: new archaeological evidence from north-west Kenya', J. Afr. Hist, xx, iii (1979), 319-28. 38 R. Soper, 'Archaeo-astronomical Cushites: some comments', Azania, xvn (1982), 145-62. 39 I n p r e v i o u s l i t e r a t u r e t h i s site is n a m e d N a m o r a t u n g a I I . H o w e v e r , since N a m o r a tunga (I) is also the name of the rock art and cemetery site, the names Kalokol and Lokori are used here to avoid confusion, following Soper, 'Cushites'. 40 41 Soper, 'Cushites', 161. Ibid. 42 H. V. Merrick and students of St Lawrence University, pers. comm. 43 Lynch and Robbins, 'Cushitic and Nilotic'. 44 Collett and Robertshaw, 'Problems'. " R. Soper, pers. comm.
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possibility exists that the Turkwel Tradition sites represent the settlements of the people buried at Lokori.46 As part of a larger project in the region to the east of Lake Turkana, Stiles has excavated ten stone burial cairns at Kokurmatakore.47 Three types of cairn are found: circular mounds, squarish platforms with buttressed corners, and rings with variant styles. Three mound cairns have been excavated; one of these, dated to the mid-second millennium b.c. (GX7421A),48 contained, among the stones forming the mound, a lava quern, obsidian artefacts and goat bones. Stiles has suggested that this first type of cairn may be related to similar cairns in the central Rift Valley and attributable to early pastoral peoples.49 Of three platform cairns excavated, one is dated to around 1000 a.d. (GX-7396A); no grave goods were found. Since similar cairns have been reported from southern Ethiopia, it is possible that those found at Kokurmatakore are the result of an early incursion of Oromo speakers into northern Kenya.50 Three dates from ring cairns range from about the fourteenth to nineteenth centuries a.d. (GX-7420A, GX-7423 A, GX-7422A); a sample of wood from adjacent to the grave fill of Gdjn3 gave a date in the region of the seventh to ninth centuries a.d. (GX-7397). Since ring cairns are made today by Eastern Cushitic speakers in the region, it is probable that they, were the makers of the excavated examples. The skeletons from these ring cairns had their lower incisors removed during life, a Nilotic practice adopted by Eastern Cushites during periods of contact.51 Several sites located in sand dunes around North Horr have been excavated by both Phillipson52 and Stiles.53 One new date is available from an undisturbed hearth 90 cm below the surface at Gcjm3; this indicates that the site was occupied some time between about 700 and 900 a.d. (GX-7395).54 However, analysis of the pottery from this and other sites at North Horr indicates that sites were probably occupied repeatedly, perhaps by people with different pottery traditions, over a considerable length of time; artefacts deposited on the dunes during these occupation episodes have been jumbled together by movement of and within the sand.55 48 This suggestion has been made previously by S. H. Ambrose, 'Archaeology and linguistic reconstructions of history in East Africa' in C. Ehret and M. Posnansky (eds.), The archaeological and linguistic reconstruction of African history (London, 1982), 104-57; see p. 121. 47 Daniel Stiles,' Preliminary results of archaeological and palaoenvirpnmental research in northern Kenya', Nyame Akuma xx (1982), 19-25; Daniel Stiles and S. C. Munro-Hay, 'Stone cairn burials at Kokurmatakore, northern Kenya', Azania xvi (1981), 151-66. 48 With the exception of GX-7397, all dates from the cairns excavated by Stiles were obtained from samples of bone apatite from the human skeleton in each cairn. Readers should evaluate these apatite dates cautiously, particularly since calcium carbonate concentrations were often found in the vicinity of the skeletons; see Collett and 49 Robertshaw, 'Problems'. Stiles, 'Preliminary results'. 60 bl Ibid. Ibid. 52 D. W. Phillipson, 'The origins of prehistoric farming in East Africa' in B. A. Ogot (ed.), Hadith vn, Ecology and history in East Africa (Nairobi, 1979), 41-63. 63 Stiles, pers. comm. and 'Preliminary results'. 64 bb Ibid. Ibid.
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PETER ROBERTSHAW THE LAKE VICTORIA REGION
Louis Leakey first reported shell middens beside Lake Victoria in 1935 ; 56 the pottery and the tools he ascribed to the Wilton C culture.57 Recent excavations58 at several shell midden sites along the South Nyanza shore of Lake Victoria have revealed that they contain a Later Stone Age microlithic industry and pottery of what we now call the Oltome tradition.59 The associated faunal remains do not include domestic animals; however, many species of wild animals are represented in the middens, ranging from hippo and buffalo through a variety of antelope, zebra, wild pigs and birds to large numbers offish and shellfish.60 Dating of the shell middens and of the Oltome tradition generally is unfortunately problematic.61 A sample of shell from a midden at Luanda was dated to early in the fifth millennium b.c. (Pta-3139) ; 62 however, shell is considered by many to give unreliable radiocarbon dates.63 Bone apatite from the same midden was dated to late in the seventh millennium b.c. (GX-8743).64 A bone sample from the midden at Kanjera West gave a result on the apatite fraction of early in the fourth millennium b.c. (GX-8744). Finally, the site of White Rock Point was dated, similarly on bone apatite, to around the end of the third millennium b.c. (GX-8745). It seems unwise to link these sites to the aquatic tradition of Middle Africa proposed by Sutton;65 bone harpoons are not represented in the shell middens and the pottery appears to be unrelated to the wavy-line and dotted wavy-line traditions.66 Oltome pottery has also been found at Gogo Falls, where bone from a very small excavation in 1981 gave a result on the apatite fraction of early in the fourth millennium b.c. (GX-8536).67 More extensive excavations have just been completed at Gogo Falls; an extensive ash midden, some 2 m thick and probably attributable to the Elmenteitan, was discovered covering part of the site and stratified between Oltome and Early Iron Age horizons.68 Preliminary 68
L. S. B. Leakey, Stone Age Races of Kenya (Oxford, 1935), 89. Leakey, Stone Age Africa (Oxford, 1936), 69. 58 P. T. Robertshaw, D. P. Collett, D. P. Gifford and N. B. Mbae, 'Shell middens on the shores of Lake Victoria', Azania xvm (1983), 1-43. 69 Formerly known as ' Kansyore W a r e ' . For the introduction of the n a m e Oltome see David Collett and Peter Robertshaw, ' Pottery traditions of early pastoral communities of K e n y a ' , Azania x v m (1983) 107-125; also Peter Robertshaw a n d David Collett, ' A new framework for the study of early pastoral communities in East Africa', J. Afr. Hist. xxiv, iii (1983), 2 8 9 - 3 0 1 . Oltome pottery is found all around Lake Victoria, in northern Tanzania, and also in the Southern S u d a n ; see Robertshaw et al. 'Shell m i d d e n s ' . 60 See Gifford's contributions to Robertshaw et al. 'Shell m i d d e n s ' . 61 Robertshaw et al. 'Shell m i d d e n s ' . 62 A correction factor of one h u n d r e d years should be subtracted from this date to allow for isotopic fractionation in fresh water. T h e figure of one h u n d r e d years was obtained by ' d a t i n g ' m o d e r n shell from Lake Victoria (J. C. Vogel, pers. comm.). 63 M. L. Keith and G.M.Anderson, 'Radiocarbon dating: fictitious results with mollusk shells', Science CXLI (1963), 634-7. 64 The problem of bone apatite dates is discussed above and in Collett and Robertshaw, 'Problems'. All the dates from shell middens mentioned here are discussed in Robertshaw 65 Sutton,'Aquatic civilization'. et al., 'Shell middens'. 88 Collett and Robertshaw, 'Early Iron Age and Kansyore pottery: finds from Gogo Falls, South Nyanza', Azania xv (1980), 133-45. 67 88 Robertshaw et al. 'Shell middens'. Excavations by the author. 67
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sorting of the faunal remains from the ash midden shows the presence of bones of both domestic and wild animals, including fish.69 A large sample of Early Iron Age (Urewe) material was also excavated, including several iron objects, but there seems to be no evidence of iron smelting at the site. Further north, Soper has excavated at the site of Gpja 17 in Busia District; this contains Urewe pottery and dates to around the late second century a.d. (GX-8748).70 On the subject of the Early Iron Age (El A), it is perhaps worth noting here that P. R. Schmidt has published a further report on his work in north-western Tanzania; this includes the first illustrations of some of the EIA ceramics.71 SOUTHERN KENYA AND TANZANIA
A wide spectrum of research is continuing in this region, which includes the southern part of the Rift Valley and adjacent grasslands. New information is available on the Later Stone Age, the prehistory of the early pastoral communities, and on the Early and later Iron Age. In southern Tanzania an early Later Stone Age (LSA) industry termed the Kiwira has been identified from the site of Kala Waterfall.72 This quartz industry is characterised by small irregular scrapers, and some use of prepared core technique. No date is available, though the geomorphology of the site suggests occupation during the Late Pleistocene or early Holocene.73 Further north, Mehlman has excavated witness sections in the very important sites of Mumba-Hohle and Nasera Rock originally dug many years ago by the Kohl-Larsens74 and Louis Leakey75 respectively. Middle Stone Age artefacts associated with anatomically modern human molars in Bed VI at Mumba" have been dated in excess of 100,000 years by uranium series analyses of bone. Bed V has produced a stone industry intermediate in character between the Middle and Later Stone Age; a bewildering series of uranium series and radiocarbon dates (ISGS-498, GX-6620A, GX-6621A, GX-6622A) suggests an age of perhaps 30,000 years or older. Human bone from a burial in the upper part of Bed III and charcoal associated with it have given dates around the beginning of the third millennium b.c. (UCLA-1913, FRA-i). Upper Bed III contains pottery of the Oltome tradition, but the association between the pottery and the burial is uncertain. A date around the late second century a.d. (ISGS-565) from the top of Bed III relates either to the end of the Later Stone Age or to Lelesu pottery of the Early Iron Age. Only the upper levels at Nasera Rock have yielded information of interest " The bones are being studied by Fiona Marshall. 70
R. Soper, pers. comm. P. R. Schmidt, 'Early Iron Age settlements and industrial locales in West Lake', Tanzania Notes and Records, nos. 84-5 (1980), 77-94. 78 Thomas Wynn and Thomas Chadderdon,' The Kiwira Industry and the Later Stone Age of the Nyakyusa Basin', Azania xvn (1982), 127-43. ' 3 Ibid. 74 L. Kohl-Larsen, Auf den Spuren des Vormenschen (Stuttgart, 1943). 76 Leakey, Stone Age Africa, 58 ff. 78 The information on Mumba-Hohle is drawn from M. J. Mehlman, 'Mumba-Hohle revisited: the relevance of a forgotten excavation to some current issues in East African prehistory', World Archaeology XI (1979), 80-94; a n d Mehlman, pers. comm. I am very grateful to Mike Mehlman for providing me with much information on his work at both Mumba and Nasera. 71
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PETER ROBERTSHAW 36 I
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Figure 2. Southern Kenya and Northern Tanzania 1. Luanda, White Rock Point 2. Kanjera West 3. Gogo Falls 4. Gpja 17 5. Prospect Farm 6. Mumba-Hohle 7. Nasera Rock 8. Lukenya Hill
9. 10. 11. 12. 13. 14. 15.
Nderit Drift Marula Rock Shelter Enkapune ya Muto Ngenyn Prolonged Drift Rigo Cave Ngamuriak, Lemek North-East, Oldorotua 16. New Mara Bridge
17. 18. 19. 20. 2i. 22. 23. 24.
Gol Kopjes (Hcje 1) Saghassa Ithanga Hills, Kwamboo Kithiru Engaruka Shanga, Pate, Manda, Lamu Mombasa Mtambwe Kuu
to readers of this journal.77 Levels 7 and 6 have produced an artefact assemblage in which there are no microliths but in which bipolar and other Later Stone Age core technologies predominate. Labelled the Naseran Industry, it is dated by various techniques, including radiocarbon (GX-6619A, ISGS-425, ISGS-500), to somewhere in the region of 22,500 years. The earliest assemblages with microliths occur around 21,500 years ago (ISGS-445). They are overlain by an assemblage which Louis Leakey called 'Capsian' dating to perhaps 18,000 to 20,000 years (ISGS-449, GX-6618A). " Mehlman, pers. comm. and 'Excavations at Nasera Rock, Tanzania', Azania xn (1977), 111-18; J. L. Bada, 'Racemization of amino acids in fossil bones and teeth from the Olduvai Gorge region, Tanzania, East Africa', Earth and Planetary Science Letters LV, 292-8.
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The earliest pottery at Nasera Rock belongs to the Oltome Tradition but is inconclusively dated (ISGS-444). Akira pottery found near the top of the sequence has been dated to the late first millennium b.c. (ISGS-438). Two radiocarbon analyses on bone apatite associated with a Later Stone Age microlithic assemblage from Lukenya Hill (Gvjm 46) near Nairobi have given readings of around 20,000 years (GX-5349, GX-5350). Underlying this assemblage is an earlier, as yet undated occurrence of LSA artefacts lacking microliths.78 While our knowledge of the transition from the Middle to the Later Stone Age remains somewhat scanty, we are at least beginning to possess a much better understanding of the Holocene sequence in the Central Rift. Ambrose, Hivernel and Nelson79 have defined four phases of the Eburran Industry80 on the basis of typological frequencies and mean microlith lengths, which span the period roughly from the eleventh to the end of the fourth millennium b.c. Four dates are given in Ambrose et a/.,81 which have not previously been reported in this journal, for various occurrences at Nderit Drift. The earliest of these (GX-4314) relates to an industry with micropercoirs (small boringtools) and thus provides a lower limiting date for the Eburran as a whole. Further work on the Eburran is being undertaken by Ambrose,82 who has excavated two sites near Lake Naivasha. At Marula Rock-Shelter an Eburran phase 3 assemblage is associated with faunal remains of species from a variety of habitats ranging from grassland to montane forest. Two dates have been processed from samples of bone apatite; the younger of these (GX-6762) is rejected by the excavator.83 The older date, in the late sixth millennium b.c. (GX-6763), is supported by geomorphological evidence concerning the fall of Lake Naivasha from its maximum level, when it drowned the site, around 9000 years ago.84 The site of Enkapune ya Muto contains well-stratified deposits spanning perhaps the last 20,000 years. The material excavated is currently undergoing analysis and only two dates are yet available. An Eburran phase 4 assemblage from a pre-pottery level has been dated to the mid-fourth millennium b.c. (GX-9399).85 This is the first date on charcoal from an in situ archaeological occurrence that confirms prehistoric settlement in this area during the middle Holocene dry phase suggested from a core drilled in Lake Naivasha.86 The other date (GX-9398), from somewhat higher in the sequence at the same site, is rejected by Ambrose as too young.87 Ambrose's investigations suggest that Eburran hunter-gatherers preferred to settle on the montane forest/savanna ecotone whence they could exploit both 78
S. F. Miller, 'LukenyaHill, Gvjm46, excavation report', Nyame Akumaxiv (1979), 3'-478 S. H. Ambrose, F. Hivernel and C. M. Nelson, 'The taxonomic status of the Kenya Capsian', in Leakey and Ogot (eds.), Proceedings, 248-52. 80 Formerly known as the Kenya Capsian. 81 Ambrose et al. 'Taxonomic status'. 82 Stanley Ambrose, pers. comm. I am very grateful to Dr Ambrose for supplying the information contained in this paragraph. 83 Ambrose (pers. comm.), points out that the absence of collagen in this bone sample indicates a much older age than the apatite reading suggests. 84 J. L. Richardson and A. E. Richardson, 'History of an African Rift Lake and its climatic implications', Ecological Monographs XLII (1972), 499-534. 86 86 Ambrose, pers. comm. Ibid.; Richardson and Richardson, 'History'. 87 Ambrose (pers. comm.) suspects the charcoal sample may have been contaminated by younger carbon.
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environments. Ambrose argues that Eburran communities may have continued to exist after the arrival of early pastoral communities in the region during perhaps the second or first millennium b.c.88 Four L.S.A. ceramic traditions associated with domestic animals have been recognized in the Central Rift and adjacent regions.89 Rapid advances continue to be made in our knowledge of these early pastoral communities; recent results are presented below in the form of a north-to-south survey. At Ngenyn, west of Lake Baringo, stone tools and pottery not yet assigned to any particular tradition were found in three archaeological occurrences associated with faunal remains from both wild and domestic species. Two of the occurrences are dated to around the end of the first millennium b.c. (Birm-767, Birm-77o, UCLA-1322).90 A similar mix of wild and domestic animals is represented in the very large faunal assemblage excavated at the site of Prolonged Drift.91 There is only a small sample of pottery from the site and this is inadequate for taxonomic purposes. Five (WSU-1203, 1204, 1234, 1237, 1242) out of seven radiocarbon dates are rejected as too young;92 the remaining pair of bone dates (GX-5375) suggest occupation during the mid-first millennium b.c.93 Gifford has provided a provocative set of models of subsistence and settlement practices to account for the composition of the faunal assemblage from Prolonged Drift.94 At Rigo Cave, close to the famous Njoro River Cave excavated by M. D. Leakey,95 stone bowl fragments were found on the surface of the deposit. Excavations yielded few artefacts, though these did include two beads similar to specimens from Njoro River. Numerous fragments of human bone were recovered; a paired bone date (GX-8026) on a human tibia gave an age in the mid-first millennium b.c.96 Investigations into the later prehistory of the Loita-Mara region of south-western Kenya have so far been centred on the Lemek Valley.97 Nearly one hundred sites have been found in this area through both systematic and casual survey. The contents of many of these sites are assignable to the Elmenteitan tradition. Four obsidian hydration dates for three Elmenteitan sites along the Oldorotua stream indicate settlement during the latter part of the first millennium b.c. and the first few centuries a.d. Excavations at 88
Ambrose, as cited in n. 46, pp. 124-5. Collett and Robertshaw, 'Pottery traditions'; Robertshaw and Collett, 'New framework'. • 90 F. Hivernel, 'Excavations at Ngenyn (Baringo District, Kenya)', Azania xvm (1983), 45-7991 This site may be Long's Drift, the type site of the 'Kenya Wilton', excavated by Leakey, The Stone Age Cultures of Kenya Colony (Cambridge, 1931); see D. P. Gifford, G. LI. Isaac and C. M. Nelson, 'Evidence for predation and pastoralism at Prolonged Drift: a Pastoral Neolithic site in Kenya', Azania xv (1980), 57-108. 92 93 Indeed four of these are 'modern'; Gifford et al. 'Evidence'. Ibid. 94 Ibid. Gifford is also actively involved with the examination and interpretation of faunal assemblages from other early pastoralist sites. 95 M. D. and L. S. B. Leakey, Excavations at the Njoro River Cave (Oxford, 1950). 96 S. Wandibba, 'Excavations at Rigo Cave in the Central Rift Valley, Kenya', Azania xvm (1983), 81-92. 97 Fiona Marshall and Peter Robertshaw, 'Preliminary report on archaeological research in the Loita-Mara region, S.W. Kenya', Azania xvn (1982), 173-80. 89
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Ngamuriak, another Elmenteitan site, have produced part of the floor plan of a burnt and collapsed hut. Large collections of stone artefacts and pottery from this site are complemented by a faunal assemblage comprising almost entirely domestic cattle, sheep and goats.98 The site seems to have been occupied around the end of the first millennium b.c. (GX-8533, GX-8534). The nearby site of Lemek North-East has yielded, by contrast, a pottery assemblage belonging to the Oldishi tradition but dating again to the late first millennium b.c. (GX-8532). The faunal remains are, as at Ngamuriak, dominated by domestic animals." While chemical analysis of the obsidian artefacts, which predominate at all these sites, shows that the obsidian originated in the central Rift Valley,100 petrographic and other analyses indicate that the pottery was produced locally.101 There is a surprising absence of evidence for any settlement in the Lemek valley between the first centuries a.d. and the nineteenth century. Expansion of the tsetse-fly belt may be responsible for this apparent hiatus, though other possibilities, including sampling bias in the survey, are under investigation. North-west of the Lemek valley the site of New Mara Bridge (Guje 12) beside the Mara River has yielded pottery that may represent a later development of the Elmenteitan associated with domesticated fauna and rare stone artefacts. A paired bone date suggests occupation in the mid-first millennium a.d. (GX-8535).102 The Elmenteitan sites in the Lemek valley, with their preponderance of bones of domestic stock, stand in marked contrast to the probable Elmenteitan occurrence at Gogo Falls where a wide range of species is represented. Site catchment analysis of Ngamuriak also indicates that agriculture may well have been practised and this may have been the case at Gogo Falls as well.103 More concretely, the discovery of these Elmenteitan occurrences invalidates the notion that Elmenteitan settlement was restricted to the Mau Escarpment and adjacent Rift Valley.104 Less is known as yet of the region to the south of Lemek; Bower has recently excavated sites in the Serengeti tested by him in previous years.105 An open site in the short-grass plains and a rock-shelter in wooded country contained similar series of occupation horizons comprising a Later Stone Age level without domestic fauna, two horizons attributed to early pastoral communities, and a later Iron Age horizon. Boulder structures at the open site are probably associated with a late stage of the upper early pastoral occupation.106 While dates of the mid sixth and late fifth millennium b.c., reported previously,107 had tentatively been thought to bracket the appearance of domestic stock at the Gol Kopjes site (Hcje 1), the new excavations have 98
Ibid., and Marshall, in preparation. •• Ibid. Brown and Merrick, pers. comm. 101 J. Langdon and P. Robertshaw, in preparation. 102 Marshall and Robertshaw, 'Preliminary report'. 103 Robertshaw and Collett,' The identification of pastoral peoples in the archaeological record: an example from East Africa', World Archaeology xv, i (1983), 67-78. 104 S. H. Ambrose, 'Elmenteitan and other Late Pastoral Neolithic adaptations in the central highlands of East Africa', in Leakey and Ogot (eds.), Proceedings, 279-82. 105 J. R. F. BowerandP. Gogan-Porter,'Prehistoric cultures of the Serengeti National Park, Tanzania', Papers in Anthropology, No. 3, Iowa State University (1981); loe Bower, pers. comm. Mgomezulu, 441. 107 Mgomezulu, 441. 100
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yielded preliminary results that are not entirely consistent with this interpretation.108 There has in general been less research conducted in recent years on the Iron Age of Kenya and Tanzania than on the preceding period. However, some new information is of considerable interest, particularly the discovery by Collett109 of an iron-smelting site at Saghassa in the Taita Hills of south-eastern Kenya. Two types of furnaces, shaft and bowl, were found, both of which contained finger-decorated bricks in their walls. These furnaces are well preserved and seem to occur in pairs. No date is yet available, but the associated pottery is closely akin to the Early Iron Age pottery found at Kwale dating to about the third century a.d.110 A total of 130 Iron Age sites were located in the Ithanga Hills in the Eastern Highlands of Kenya in a survey conducted by Mahlstedt and DiBlasi.111 Three of these sites can be attributed to the Kwale group of the Early Iron Age industrial complex. Excavations at one of the sites, Kwamboo, have yielded a ceramic assemblage showing both similarities to and differences from the pottery from Kwale itself. Two radiocarbon dates indicate occupation around the beginning of the third century a.d. (GX-7020, GX-7O2i).112 This suggests that Early Iron Age farmers had settled extensively in the Eastern Highlands probably early in the first millennium a.d. Further support for this hypothesis is provided by a surprisingly early date, falling in the first half of the first millennium a.d. (GX-8746), for Gatung'ang'a pottery from the site of Kithiru in Meru District.113 It seems probable that Gatung'ang'a pottery develops from Kwale ceramics.114 Engaruka, with its terraced villages and field systems, is perhaps the best-known later Iron Age site in East Africa.115 Seven out of nine dates obtained previously by Sassoon fell in the mid to late second millennium a.d.;116 however, the remaining two dates, from Sassoon's 'hillside village 3', suggested the possibility of an earlier occupation in the first millennium a.d. of at least part of the complex.117 Recent excavations in this same village by the author have led to the dating of three charcoal samples, all of which gave results within the last four hundred years (HAR-5475, HAR-5476, 108 110
109 Bower, pers. comm. Collett, pers. comm. R. Soper, 'Kwale: an early Iron Age site in south-eastern Kenya', Azania 11
(1967), 1-17. 111 T. F. Mahlstedt and M. C. DiBlasi, 'Archaeological survey of the Ithanga Hills, Eastern Highlands of Kenya: preliminary analysis', Azania xm (1978), 192-3. 112 DiBlasi, 'Kwamboo: an Early Iron Age occurrence in the Eastern Highlands of Central Kenya', paper presented at the seventy-ninth annual meeting of the American Anthropological Association, Washington, D.C. (1980). 113 R. Soper, pers. comm. The dates for Gatung'ang'a itself suggest occupation around the eleventh century a.d.; A. Siiriainen, 'The Iron Age site at Gatung'ang'a, central Kenya', Azania vi (1971), 199-232. 114 R. Soper, pers. comm. and 'Iron Age pottery assemblages from central Kenya', in Leakey and Ogot (eds.), Proceedings, 342-3. 116 For the most recent account of the site see J. E. G. Sutton, 'Engaruka and its waters', Azania xm (1978), 37-70. 116 H. Sassoon, 'Excavations at Engaruka, northern Tanzania', National Geographic Society Research Reports for ig6s (1971), 221-30. 117 See, for example, Roland Oliver, 'The East African interior', in R. Oliver (ed.), Cambridge History of Africa, vol. 3: c. 1050 to c. 1600 (Cambridge, 1977), 621-69, a t pp. 653-4.
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118
HAR-5477). Unfortunately all these dates fall in the period when there are pronounced kinks in the dendrochronological calibration curve, so that the only thing that can be stated with reasonable certainty is that all the dates are post-A.D. 1500.U9 One charcoal sample, HAR-5477, came from more than 150 cm below the surface of one of the terraces. In view of this and the fact that the pottery found in the new excavations does not appear to indicate the presence of any developmental sequence, the first millennium a.d. dates obtained by Sassoon should be discounted as dating the occupation.
THE EAST AFRICAN COAST
Recent excavations at Shanga and at Pate have produced results which, when combined with those from Chittick's work at Manda,120 have an important bearing on our understanding of the origins of coastal settlement and the genesis of Swahili culture. As at Manda, occupation at Shanga seems to have begun around the ninth century a.d. (Q-3061, Q-3064, Q-3066),121 with imported pottery and glass found in all levels.122 It appears that the earliest buildings were constructed from timber and daub, and that the use of stone was a later development.123 It is also reported that there is little evidence for the impact or presence of Islam at Shanga before the eleventh century.124 The settlement seems to have been occupied continuously until late in the fourteenth century, when it was abandoned for reasons as yet unknown. A burnt roof timber from a mosque has been dated to the late thirteenth century a.d. (Q-3065).125 Two test pits excavated by Wilson at Pate have produced a sequence which closely parallels that from nearby Shanga.126 Though no radiocarbon date is available, the deposits can be tied to absolute dates by means of the imported pottery. This indicates that the earliest levels are probably contemporary with those of Shanga, and may be the remains of mud and thatch buildings. These results clearly negate the argument that Pate was non-existent, or of negligible size before about A.D. 1300.12' It now seems almost certain that a number of settlements, including Shanga, Pate and Manda, were founded on the Eastern African coast around the ninth century A.D. These settlements extended from at least as far north as the Lamu archipelago to Chibuene in Mozambique in the south.128 For East Africa there is no archaeological evidence for any earlier coastal 118
Robertshaw, unpublished data.
119
See Stuiver, as cited in n. 8, p. 8.
180 Mgomezulu, 448; Neville Chittick, Excavations at Manda (Nairobi, 1984). 121 Mark Horton, pers. comm. 122 Mark Horton (compiler), Shanga ig8o: an interim report (Nairobi, 1980); idem, ' Some archaeological problems regarding the genesis of Swahili culture', paper presented to African history seminar, S.O.A.S., London, 1981. 123 Horton, 'Archaeological problems'. 126 Ibid. 188 T. H. Wilson, pers. comm. I am most grateful to Dr Wilson for providing me with detailed results of his work at Pate and elsewhere. 127 Neville Chittick, 'A new look at the history of Pate', J. Afr. Hist, x, iii (1969), 375-91, especially p. 378. 128 Paul Sinclair,' Chibuene - an early trading site in Southern Mozambique', Paideuma XXVIII (1982), 149-64.
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occupation. Trade may have been an important factor in the establishment of these seaward-facing settlements. However, what is perhaps remarkable is the uniformity of the earliest local pottery from all the sites, including Chibuene; for example, some vessels from Chibuene appear identical to vessels from the first period at Manda. Disagreement exists as to whether the coastal towns were established by immigrants from the Persian Gulf130 or by proto-Swahili Bantu spreading south from Somalia.131 Rescue excavations carried out before the construction of a new hospital have provided our first archaeological evidence of the town of early Mombasa.132 Five dates from the lower levels fall between the early tenth and late eleventh centuries a.d. These dates are regarded as a little too early by Sassoon who, on ceramic evidence, would date these deposits to between A.D. IOOO and A.D. 1200.133 The first stone walls were built probably in the first half of the thirteenth century A.D. Occupation, at least in the area excavated, ceased around A.D. 1500. This may be correlated with the destructions of the town in 1505 and 1528 known from written sources.134 Also on Mombasa Island, Sassoon has investigated the mosque and the curious, tapering tower at Mbaraki.135 From pottery finds and historical records it appears that the mosque was built about the middle of the fifteenth century A.D. and was used for its original purpose only until the early sixteenth century. As a ruin it was later used for 'spirit worship'. The pillar was erected around A.D. 1700, probably 'as a centre for consultations with the spirit world, for which purpose it is used at the present day'. 136 On the island of Pemba in Tanzania the site of Mtambwe Kuu has been dated to the eleventh to thirteenth centuries A.D. on the basis of imported potsherds.137 Chittick also visited Unguja Ukuu on Zanzibar, where pottery similar to that from Manda indicates occupation around the tenth century.138 A reconnaissance in the Rufiji Delta failed to reveal any trace of the elusive site of Rhapta mentioned in the Periplus.139 The tombstone of Sultan Muhammad Fumo Madi, an important figure in the Pate Chronicle, has been found in Lamu.140 The inscription was originally reported by Stigand in 1913 before the stone was lost.141 However, Stigand mistakenly read the correct date of A.H. 1224 (A.D. 1809)142 as A.H. 1004 (A.D. 129 However, rare shell ornaments from the coast werefindingtheir way inland probably as early as the first millennium b.c.; for a brief summary of the evidence see Chittick, 'Archaeology in Eastern Africa', in D. I. Ray, P. Shinnie and D. Williams (eds.), Into the 80s: the proceedings of the eleventh annual conference of the Canadian Association of African 130 Chittick, Manda. Studies, Vol. 1 (Vancouver, 1981), 20-36, see p. 33. 131 See, for example, Derek Nurse, 'A linguistic reconsideration of Swahili origins', Azania xvin (1983), 127-50. Of course the question of origins need not be of the 'either/ or' sort; indeed a compromise view may well be the most satisfactory. 132 Hamo Sassoon,' Excavations at the site of Early Mombasa', Azania xv (1980), 1-42. 133 Ibid. 38. A sixth date with a result around the late sixth century a.d. (N-3219) is 134 rejected completely by Sassoon, 'Excavations', 39. Sassoon, 'Excavations'. 136 Hamo Sassoon, ' The mosque and pillar at Mbaraki: a contribution to the history 136 Ibid. 96. of Mombasa Island', Azania xvn (1982), 79-97. 137 Chittick, 'Reconnaissance in coastal Tanzania', Nyame Akuma xx (1982), 57-8. 138 139 Ibid. Ibid. 140 T |_j Wilson, pers. comm. 141 C. H. Stigand, The Land of Zinj (London, 1913), 163. 142 Verified by Wilson.
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143
1615—16). Since the Pate Chronicle reports the Sultan's death as occurring in A.H. 1224, the inscription verifies one item in the Chronicle.144 Finally, on the regional scale, it is worth noting that attempts are being made to elucidate the development of the Swahili coast by using site lists and spans of occupation for each site.145 In addition, consideration of environmental variables, such as the location of harbours, sources of fresh water, and areas with agricultural potential, promises to aid our understanding of the nature of coastal settlement at different periods.146 MALAWI
There are very few new radiocarbon dates from Malawi. However, the pace of research has not slackened, and several interdisciplinary projects involving archaeology are being pursued. Geomorphological studies of high lake levels of Lake Malawi are being tied to archaeological sequences established by excavations along the lake shore. Four periods of high lake levels, the latest in 1980, are now known to have occurred in the last 2000 years from work at Senga Bay, Namaso Bay and Liwonde on the Upper Shire River.147 Two of these periods can be correlated approximately with Mawudzu pottery dating from about the mid-twelfth to mid-eighteenth centuries a.d., while the earliest occurs shortly before the appearance of Nkope pottery in the third century a.d. Excavations in the Shire Highlands are providing new information on Iron Age settlement. A date in the tenth century a.d. (Har-3798) from Chirombo Village Site is the earliest so far available for both Kapeni and Nkopi pottery on the Shire Highlands. It seems that both types of pottery were simultaneously introduced to this region by people who had already established themselves in the Shire Valley and Chilwa—Phalombe Plain some time between the sixth and eighth centuries a.d.148 Longwe pottery has been found at Midima rock-shelter in association with sorghum seeds.149 A date early in the eleventh 143 144
Stigand's reading was doubted by Chittick, 'New look', 386-7. Chittick, 'New look', 391, writing of the Pate Chronicle, is 'doubtful whether
anything useful can be deduced from these dreary catalogues'. However, Allen is not so pessimistic as to the value of 'that much maligned document'; J. de V. Allen, 'The "Shirazi" problem in East African coastal history', Paideuma xxvm (1982), 9-27 (at p. 23). 145 -p. H. Wilson, 'Spatial analysis and settlement patterns on the East African coast', Paideuma xxvm (1982), 201-19. 148 Allen, 'Settlement patterns on the East African coast, c. A.D. 800-1900', in Leakey and Ogot (eds.), Proceedings, 361-3; idem, 'Swahili culture and the nature of east coast settlement', International Journal of African Historical Studies xiv, ii (1981), 306-34; T. H. Wilson, 'Settlement patterns of the coast of Southern Somalia and Kenya', paper presented to the first International Congress of Somali studies (Mogadishu, 1980). 147 R. Crossley and S. Davison-Hirschmann, 'Hydrology and archaeology of Lake Malawi and its outlet during the Iron Age', Palaeoecology of Africa xm (1981), 123-6; Crossley and Davison-Hirschmann, 'High levels of Lake Malawi during the Late Quaternary', Palaeoecology of Africa xv (1982), 109-15. 148 Y. M. Juwayeyi, 'The later prehistory of Southern Malawi: a contribution to the study of technology and economy during the Later Stone Age and Iron Age periods' (Ph.D. thesis, University of California, Berkeley, n.d.); Juwayeyi, pers. comm. I am most grateful to Dr Juwayeyi for commenting upon the significance of the dates he has obtained. 140 Juwayeyi, 'Later prehistory' and pers. comm.
388
PETER ROBERTSHAW 24°
26'
24'
26°
28°
30°
32°
10°-
12°-
14°-
16°-
28°
30°
32°
Figure 3. Zambia and Malawi 1. 2. 3. 4.
Liwonde Chirombo Village Midima rock-shelter Kasungu National Park
5. Mwambachimo 6. Mufulwe 7. Chilimulilo
8. Luano 9. Kalongola 10. Kala Waterfall
century a.d. (Pta-2804) is compatible with other dates for Longwe pottery;150 this is the earliest evidence so far available for agriculture in the Shire Highlands. A survey of the Kasungu National Park in central Malawi has revealed about ninety sites, only one of which appears to have in situ Early Iron Age pottery (Nkope).151 Excavations have concentrated on the later Iron Age smelting-furnaces. Numerous very tall (2^-3 m) induced-draught furnaces were found in the region but very few of them are associated with large amounts ( > 30 tons) of slag. Since the local laterites are so low in iron content, it seems that these large furnaces served as concentrators to produce iron-rich sponge.152 Although local iron-smelting seems to have ended in Malawi around 1930, Avery and van der Merwe recently persuaded Phoka and Chewa men who had been apprentice smelters in their youth to re-create their past. Both groups conducted successful smelts by induced draught. Most notable perhaps is the fact that it appears to take about 1000 kg of charcoal from carefully selected species of hardwoods to produce two to four hoes.153 A large number of fortified villages (michena), apparently dating to the period of Ngoni incursions in the nineteenth century, have also been found 160 152
161
Mgomezulu, 451. Ibid.
163
D. Killick, pers. comm. N. J. van der Merwe, pers. comm.
ARCHAEOLOGY IN EASTERN AFRICA
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in the Kasungu Park. These villages are very tightly packed with hut mounds, and are surrounded by earthen walls and ramparts. They vary greatly in size, from about 2500 m2 to six hectares.164 ZAMBIA
Excavations in rock-shelters on the southern edge of the Copperbelt have produced a culture-historical sequence spanning the last 18,000 years.155 At Mwambacimo a series of microlithic assemblages assignable to the Nachikufan have been discovered. Nachikufan I assemblages date between 18,000 years ago and the early seventh millennium b.c. (Pta-2453, Pta-2454, N-3434, N-3435), of which Phase IIA is dated to the early fourth millennium b.c. (Pta-2410, N-3433). Early Iron Age pottery is found in the Nachikufan III levels together with microlithic stone artefacts; two dates fall in the early tenth and seventeenth centuries a.d. (Pta-24oa, N-3432).158 Dates in the late third century b.c. and the early tenth century a.d. (Pta-3255, 3256) from the site of Mufulwe are reported to document the appearance of Early Iron Age pottery within deposits containing a microlithic industry. Three other dates (Pta-3257, 3258, 3259) for lower levels at Mufulwe are considered by the excavator to be too recent to date the microlithic assemblages with which they had been thought to be associated. For the same reason two dates (Pta-2180, 2181) are rejected as dating the lower levels at Chilimulilo. Numerous sites have been found in the vicinity of the Luano hot spring near Chingola, on the Copperbelt. The sites contain deposits ranging from the later Iron Age to the Middle Stone Age, including an Early Iron Age village with preserved hut floors. No date is yet available from excavations in several sites. Preliminary results indicate that the Early Iron Age ceramics belong in the Chondwe group. There is a clear typological continuity between the Early and later Iron Age assemblages, suggesting also continuity of population.157 Research in the Upper Zambezi valley has demonstrated the division of the region into western and eastern streams of the Early Iron Age by about the fifth century a.d.158 Ten dates are available from the site of Kalongola near Senanga, containing ceramics of the western stream of the Early Iron Age. Occupation appears to span the period between the mid-fifth and the late tenth centuries a.d.159 154 156
Killick, pers. comm. F. B. Musonda, 'Aspects of the prehistory of the Lunsemfwa Drainage Basin,
Zambia, during the last 20,000 years' (Ph.D. thesis, University of California, Berkeley, 1983); F. B. Musonda, 'Late Pleistocene and Holocene microlithic industries from the Lunsemfwa Drainage, Zambia', South African Archaeological Bulletin xxxix (1984), in press; F. B. Musonda, 'Excavations at three rockshelter sites in the Copperbelt Province of Zambia', Nyame Akuma xvn (1980), 75-6. 166 Pta-2409 was reported in Mgomezulu, 452. 167 M. S. Bisson, 'Preliminary report on the Luano archaeological survey', Nyame Akuma xix (1981), 37-9. 168 N. M. Katanekwa, pers. comm. 168 Katanekwa, pers. comm.; J. S. Jambo,' Zambia National Monuments Commission: archaeological research activities in 1982', Nyame Akuma xxn (1983), 34.
390
PETER ROBERTSHAW SUMMARY
Obsidian hydration dating has been successfully applied to East African archaeological sites. Chemical sourcing of obsidian artefacts has documented long-distance movement of obsidian from the Central Rift valley. A date in the ninth or eighth century b.c. has been obtained for iron objects in the Er Renk District of the Southern Sudan. Tentative culture-historical sequences are available from excavations around the Sudd and in the Lake Besaka region of Ethiopia. Archaeological research has begun in the interior of Somalia. In northern Kenya, claims that Namoratunga II is an archaeo-astronomical site have been challenged. Excavations at Mumba-Hohle and Nasera have shed new light on the transition from the Middle to Later Stone Age in northern Tanzania perhaps 20,000 to 30,000 years ago. Knowledge of the Elmenteitan Tradition has been considerably advanced by excavations in south-western Kenya. Iron-smelting furnaces with finger-decorated bricks have been discovered in south-eastern Kenya, though not yet dated. New dates falling in the last few centuries have caused first millennium a.d. dates obtained previously for Engaruka to be rejected. Excavations at several sites on the East African coast indicate that the beginnings of coastal occupation from the Lamu archipelago to Mozambique fall in the ninth century a.d. In Malawi the Shire Highlands seem to have been settled around the tenth century a.d. Investigations of large smelting-furnaces in central Malawi indicate that they were used as concentrators of poor-quality iron ore. Excavations in rock-shelters on the southern edge of the Copperbelt have produced a culture-historical sequence spanning the last 18,000 years. The western stream of the Early Iron Age was established in the Upper Zambezi valley by about the mid fifth century a.d.
APPENDIX
List of new archaeological radiocarbon dates based on 5,570-year half-life. All samples charcoal unless indicated as follows: (A) apatite, (C) collagen, (S) shell, (OE) ostrich eggshell. An asterisk denotes a bone or shell date that has not been corrected for C13 fractionation. Ethiopia Fejx4, Lake Besaka UW-492 (OE): b.c. 16,500 + 225 UW-493 (OE): b.c. 17,510 + 205 UW-494(OE): b.c. 17,330 + 215 UW-495 (OE): b.c. 20,130 + 305 Fejx2, East, Lake Besaka *SUA-469A (A): b.c. 4340+ 150 *SUA-469B (C): b.c. 4 3 7 0 + n o *SUA-47o(C): b.c. 3600+110 nJCR-483 (C): b.c. 2800+170
Fejx2, Lake Besaka I-8330: b.c. 2835 + 120 *UCR-482 (C): b.c. 1600+ 165 *SUA-468A (A): b.c. 1530+150 *SUA-468B (C): b.c. 235 + 210 *UCR-48i (C): b.c. 620 ± 160 Fejx3, Lake Besaka I-7969: b.c. 1510 + 280
Somalia Medishe 2 UW-761: > b.c. 38,050 UW-787: b.c. 16,920 + 340
Gud-Gud UW-762: >b.c. 38,050
Karin Hagin UW-763: a.d. 323 ± 130 UW-764: b.c. n o ± 6 5
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Southern Sudan Debbat El Eheima, Upper Nile Kat, Lakes Province Hel-1553: Modern Province Hel-1554: Modern T-4811 (S): b.c. i3so±6o Bekjiu, Lakes Province T-5032 (S): b.c. ii9o±8o Hel-1547: a.d. 880+100 T-4562: b.c. 810 + 70 Hel-1548: a.d. 870+100 Debbat Bangdit, Upper Nile Hel-1549: a.d. 640 + 90 Province Hel-iS55: a.d. 740 + 90 T-5063 (S): a.d. 75O±8o Hel-iss6: a.d. 650 + 90 T-5064 (S): a.d. 700 + 70 Hel-1557: a.d. 1110 + 90 T-5065: a.d. 350+140 T-5066: a.d. 1610+110 Na'am, Lakes Province T-S067: a.d. 850 ±80 Hel-1550: Modern T-5068: a.d. 610+130 Hel-1551: Modern Hel-1552: Modern Northern n.enya Kenya Abalete Akoit (Fwjh 16), Turkana Kokurmatakore (Gdjn 3), Eastern Province District GX-7397: a.d. 840+ 155 GX-8747: b.c. 1420+190 GX-742o(A): a.d. 13651115 Kokurmatakore (Gdjn 4), Eastern Kokurmatakore (Gdjn 6), Eastern Province Province GX-7421 (A): b.c. 1510+155 GX-7422 (A): a.d. 1440+115 Kokurmatakore (Gdjn 2), Eastern Kokurmatakore (Gdjn 5), Eastern Province GX-7396 (A): a.d. 990+ 190 Province GX-7423 (A): a.d. 1825! 120 North Horr (Gcjm 3), Eastern Province GX-7395: a.d. 800+110 Lake Victoria Region Gogo Falls, South Nyanza, Kenya Luanda, South Nyanza, Kenya GX-8536 (A): b.c. 38551185 Pta-3139 (S): b.c. 4790 + 80 Ganga (Gpja 17), Busia, Kenya GX-8743 (A): b.c. 6290 + 245 GX-8748: a.d. 190+160 Kanjera West, South Nyanka, Kenya GX-8744 (A): b.c. 3895±310 White Rock Point, South Nyanza, Kenya GX-8745 (A): b.c. 20651260
Southern Kenya and Tanzania *ISGS-566(OE):b.c. 25,010 Mumba-Hohle, northern Tanzania + 760 GX-6623 (A): b.c. 17,8701750 FRA-i (C): b.c. 2940 + 70 GX-6622 (A): b.c. 19,0451680 UCLA-1913: b.c. 2910I100 GX-6621 (A): b.c. 27,620:^ ISGS-565: a.d. 170180 *ISGS-498 (S): b.c. 29,1201500 GX-6620 (S): b.c. 35,050 (no Nasera Rock, Serengeti, Tanzania standard deviation given) *ISGS-5OO (A): b.c. 15,130+130 *ISGS-499 (S): b.c. 34,950 + 800 *ISGS-5oo (C): b.c. 18,410 + 330
PETER ROBERTSHAW
392
*ISGS-425 (A): b.c. 20,400 + 380 *ISGS-42S (C): b.c. 20,960 + 400 GX-6619 (A): b.c. i6,525±86o *ISGS-445 (A): b.c. 19,750 + 600 # ISGS-445 (C) : b.c. 19,650 + 400 GX6618 (A): b.c. 16,330 + 645 # ISGS-449 (A): b.c. 2O,5io±5oo •ISGS-449 (C) b.c. 12,830 + 250 *ISGS-427 (A) b.c. 6150+ 120 *ISGS-427 (C) b.c. 5i5O±75 *ISGS-444 (A) b.c. 34501150 *ISGS-444 (C) b.c. 2770+ 150
*ISGS- 43 8(A): b.c. 110+ 100 *ISGS-438(C): b.c. 230 + 200 Lukenya Hill (Gvjm 46), near Nairobi GX-5349(A): b.c. i GX-5 3 5 o(A): b.c. 16,980+SSS0 Nderit Drift, C. Rift Valley GX-4314: b.c. 10,760 + 310 GX-5136: b.c. 833o±28o GX-4214: b.c. 8735 + 270 GX-4215: b.c. io,ii5±365 Marula Rock Shelter, C. Rift Valley GX-6762 (A): a.d. 1085 + 220 GX-6763 (A): b.c. 5245±260 Enkapune ya Muto, C. Rift Valley GX-93 9 8:b.c. 380±235 GX-9399: b.c. 34i5±235 Ngenyn, Baringo, Kenya Birm-767 (C): b.c. 20+150 Birm-770: b.c. 70+ 130 *UCLA-i322(C): b.c. 1 3 0 + n o
Shanga, Lamu Q-3061: a.d. Q-3062: a.d. Q-3063: a.d.
Q-3064: Q-3065: Q-3066: Q-3067:
a.d. a.d. a.d. a.d.
Prolonged Drift, C. Rift Valley WSU-1203: Modern WSU-1204: a.d. 1830 + 200 WSU-i234(C): Modern WSU-1237 (C): Modern WSU-1242 (C): a.d. 69O± 160 GX-5375 (C): b.c. 580+160 GX-5375 (A): b.c. 365 + 150 Rigo Cave, C. Rift Valley GX-8026 (C): b.c. 460 ±125 GX-8026 (A): b.c. 495±290 Ngamuriak, Narok District, Kenya GX-8533: b.c. 185 + 140 GX-8534: a.d. 10+140 Lemek North-East, Narok District GX-8532: b.c. 275 + 140 New Mara Bridge, Emarti (Guje 12), Narok District GX-8535 (C): a.d. 56o±i5O GX-8535 (A): a.d. 635+145 Kwamboo, Machakos District, Kenya GX-7020: a.d. 220+ 130 GX-7O2i:a.d. 190+120 Kithiru (Gpjp 35), Meru District, Kenya GX-8746: a.d. 320+155 Engaruka, Monduli District, Tanzania HAR-5475: a.d. 1760 + 80 HAR-5476: a.d. 1670 + 90 HAR-5477: a.d. 1730 ±80
East African Coast Early Mombasa , Kenya District, Kenya 775 ±30 N-3214: a.d. 980 + 95 N-3215: a.d. 940 + 90 970 + 30 1120 + 30 N-3216: a.d. 1000 + 60 790 + 30 N-3217: a.d. 940+ 100 1270 + 30 N- 3 2i8: a.d. 1080 + 90 830 + 30 N-3219: a.d. 580 + 95 1080 + 30 Malawi
Chirombo Village Site, Southern Region Har-3798: a.d. 920 + 50
Midima rock-shelter, Southern Region Pta-2804: a.d. 1020 + 40
ARCHAEOLOGY IN EASTERN AFRICA
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Zambia Mwambachimo, Central Province Pta-2453: b.c. 16,130+180 N-3435: b.c. 10,050 + 90 N-3434: b.c. 10,950+110 Pta-2454: b.c. 6880 + 90 N-3433: b.c. 3890+ 110 Pta-2410: b.c. 4030 + 70 N-3432: a.d. 900 + 75 Mufulwe rock-shelter, Central Province Pta-3255: a.d. 1020 + 50 Pta-3256: b.c. 220 + 50 Pta-3257: a.d. 1350 + 40 Pta-3258: a.d. 490 + 40 Pta-3259: a.d. 260 + 40
Chilimulilo rock-shelter, Central Province Pta-2180: a.d. 1530 + 35 Pta-2181: a.d. i73O±35 Kalongola, Western Province Pta-3250: a.d. 810 + 50 Pta-3251: a.d. 640 + 50 Pta-3249: a.d. 480 + 50 (9429/1): a.d. 780 ±65 (9429/2): a.d. 670 + 60 (9429/3): a.d. 645 ±40 (9429/4): a.d. 970 ±90 (9429/6): a.d. 530±65 (9429/7): a.d. 690 ±50 (9429/8): a.d. 445 ±85
N.B. Numbers in parentheses are reference numbers, not official laboratory numbers.