Archaeometry and urbanism at Great Zimbabwe
沙德雷·奇瑞库 Shadreck Chirikure
(南非开普敦大学 University of Cape Town)
(英国牛津大学 University of Oxford)
Great Zimbabwe: A brief background
One of the most significant cultural innovations that developed in sub-Saharan Africa between CE1000 and 1900 is known as the Zimbabwe culture (madzimbahwe) whose prominence is attested by the presence of more than 1,000 residences built of drystone walls without any binding mortar. In terms of distribution, Zimbabwe culture settlements, production and distribution sites are mostly concentrated in southern Zambezia: a sub-continent bounded to the east by the Indian Ocean, to the west by the Kalahari Desert, to the north by the Zambezi River, and to the south by the Soutpansberg range of mountains. Evidence indicates the presence, across space and time, of multi-directional exchange networks of various intensities that linked different madzimbahwe, internally and externally, with regional processes on the wider African continent and the Indian Ocean Rim belt. The international significance of the Zimbabwe culture is brought into sharp relief by the fact that three of its former capitals, Khami (CE1450-1820), Mapungubwe (CE1220-1290) and Great Zimbabwe (CE1000-1700), are inscribed on the UNESCO World Heritage List owing to their exceptional value to humanity.
Without doubt, the most prominent Zimbabwe Culture settlement is Great Zimbabwe which emerged around CE 1000 and flourished until 1700 CE. The archaeological site of Great Zimbabwe is situated approximately 28 kilometres southeast of the modern town of Masvingo in southern Zimbabwe. Interdisciplinary research has shown that it was the capital of a powerful state which ruled a sizeable territory (approximately 50 000 and 100 000 square kilometres) in southern Africa. This globally famous dzimbahwe is comprised of multi-building settlements dispersed across an area that is more than 720 hectares in spatial extent. However, for historical and other reasons, current day boundaries of the official Great Zimbabwe estate fall within the 720 hectares, that simultaneously, are also the precincts of the National Monument and World Heritage site.
Great Zimbabwe’s multi-building settlements are clustered in different areas with and without monumental architecture. Perhaps the most well-known are the Hill Complex, the Valley Enclosures, the Great Enclosure, nearby smaller walled areas, and contiguous unwalled settlements. The Hill Complex is comprised of free-standing walls and terraced platforms on the hill slopes. The Valley Enclosures have a minor presence of terraced walls, the majority being free standing walls. The Great Enclosure is built exclusively of free-standing walls. Collectively forming drystone walled areas, the free-standing walls and terraces respectively formed enclosures and platforms where homesteads were built. They are the most imposing and visually captivating architectural ensembles within Great Zimbabwe. Besides this monumental construction, Great Zimbabwe also has settlements without drystone walls. Mostly dating to a later time period, indications are that such settlements had earthen walls that have since succumbed to the elements.
Several excavations were performed at Great Zimbabwe from the treasure hunting expeditions of the late 19th century through the professional investigations of the twentieth century. To begin with, in the late 19th century, Great Zimbabwe and related sites were believed to have been built by foreigners represented by a now vanished exotic race. While such thinking was superseded by the first three decades of the 20th century, research has since then mostly focussed on the areas with drystone walls, where initial interest by those who doubted a local origin for the site was pivoted. In addition, this also reflected a monumental bias often typical of archaeological research in different parts of the preceding century. Nevertheless, synthesising old and new excavations enabled archaeologists to delineate the evolution of settlements making up Great Zimbabwe. Consequently, it is now generally agreed that occupation associated with the builders of stone walls at Great Zimbabwe passed through four different phases: Periods II (CE900–1000), III (CE1000–1200), IV (CE1200–1700), and V (CE1700–1890). This division is only useful for analytical purposes because in practice it is difficult to separate the end of one phase from the beginning of a new one.
As hinted before, scholarly contestations prompted by whether Great Zimbabwe was local or exotic in origin, to a certain extent, shaped the major research questions which generations of researchers sought to investigate at the site. While forming a fulcrum on which future works on the site rested, it was becoming increasingly evident that such a focus was narrow, and that new research was required at Great Zimbabwe. For example, although it was clear on the basis of different strands of evidence such as glass beads, Chinese celadon, Chinese porcelain and Islamic glass, and iron gongs from central Africa, that Great Zimbabwe participated in internal and external long-distance trading networks, the dynamics of local production and circulation were poorly understood. Furthermore, on a micro scale, the activities performed in different homesteads by various households remained underexplored. Worse still, for its 720 hectares, Great Zimbabwe only had 25 generally accepted radiocarbon dates, eleven of which were derived from a single trench on the Hill Complex. Therefore, the relationships – chronological, cultural and otherwise – between areas with drystone walls and those without remained poorly understood. Furthermore, such a diachronic and synchronic lack of information on essential categories of human behaviour hindered a fuller understanding of essential issues of class relations, inequality, as well as production and circulation at Great Zimbabwe itself and on the wider landscape. This motivated for a deployment of interdisciplinary tools combining standard archaeological techniques with innovative archaeological science methods to develop high resolution chronologies and to recover material culture from neglected parts of the site such as unwalled settlements. The outcomes of such a multi-dimensional approach, when interpreted using African philosophies, permitted explorations of various behaviours set in material and non-material remains in Great Zimbabwe thereby highlighting local agency.
Approaches and Methods
Great Zimbabwe is an extant African capital replete with settlements belonging to different time periods. However, for the bulk of the time, interpretation of various behaviours attested at the site, to a large extent rested on Western derived frameworks partly developed on the basis of observations from Polynesia and other regions in the world. Somewhat, this produced knowledge that is partly at variance with local ways of knowing and understanding. This motivated for Africa-centred research that sought to explore class relations, inequality, interaction, political economy and other issues. The idea was to compare the outcomes with behaviours attested in other regions of the globe. Overall, the objective was to develop locally sensitive knowledge that resonated with African cosmos, understanding and sensibilities.
Flowing from this theoretical flavour, an interdisciplinary but stepped methodological approach was developed to pursue the research questions. In the first instance, a comprehensive library and archival study of published and unpublished material relating to Great Zimbabwe was performed. This included consulting cartographic databases housed in the Zimbabwe Museum of Human Sciences in Harare and the Great Zimbabwe Conservation Centre (GZCC). Subsequently, studies of legacy collections housed in different repositories were conducted in Zimbabwe and abroad. This produced themed maps that showed the evolution of research at the site and highlighted previously excavated sections alongside those that never attracted serious research. Dedicated geophysical surveys were performed to map buried settlement remains in unwalled areas. This information was complemented with that flowing from a LIDAR scan of the 720 hectares making up the Great Zimbabwe estate and immediate surrounds.
Thereafter, stratigraphic excavations were performed in previously unexcavated areas of Great Zimbabwe including the unwalled settlements on the western and eastern parts of the site and terraces on the southern slope of the hill. Burned bone and material from short-lived samples such as twigs was submitted for AMS dating resulting in the production of first ever Bayesian chronologies for Great Zimbabwe. Material culture recovered from the excavations included local pottery, animal bone, metal production debris, Chinese celadon, and glass beads. Inorganic material remains were studied using scientific techniques in the laboratory to reconstruct their technological and embedded social and cultural histories. Exploratory mineralogical and geochemical studies of pottery from walled and unwalled settlements were performed to determine if there were similarities and differences in the local pottery consumed by those inside and outside the walls. This was hugely significant because previously, it was argued that elites of Great Zimbabwe occupied the walls while the commoners resided in unwalled settlements.
The deployment of interdisciplinary techniques of investigation produced varied but interesting findings that took our knowledge of Great Zimbabwe and its networks to a new frontier. To begin with, a mapping of the history of past research activities highlighted how poorly explored the archaeology of the site was. For example, all the major excavations took place in the walled areas with the outcomes projected to understand behaviours taking place in unwalled settlements. This was regardless of the fact that the chronologies of unwalled settlements were poorly known. A total of 65 new radiocarbon dates were produced, the bulk of which came from unwalled areas. While still not adequate, the chronological implication of the dates was that settlement in walled areas chronologically overlapped with that in a few unwalled settlements. Most unwalled settlements were occupied after the abandonment of key drystone walled areas such as the Hill Complex. The other interesting finding was, within a context of differing chronologies, that the distribution of objects recovered and by extension activities represented was broadly comparable for both the walled and unwalled areas. For example, local pottery, spindle whorls, bronze objects, iron objects, crucibles for processing gold, glass beads, and grinding stones were found in both areas. Archaeometric analyses of crucibles and other metallurgical remains revealed that the technology employed across the walled and unwalled areas were comparable. Neither could mineralogical and geochemical analyses separate clays and vessel forming techniques used to make pottery used in walled and unwalled settlements. Consequently, other than the fact that some settlements had drystone walls and that the others lacked these, the distribution of activity areas was more or less comparable. This discrepancy can be attributed to continuity and change, where there was a decline in drystone wall construction. More importantly, the earlier assumption that elites lived in the walls while commoners resided outside the walls where they lacked access to prestige goods was not fulfilled by the data. This has consonance with African cosmologies that indicates that often elites lived with their servants while commoners lived in their own homesteads away from the centre. Continuing work will add further insights on elite commoner relations and dynamics of household production and consumption within Great Zimbabwe.
Discussion and conclusion
Without doubt, Great Zimbabwe is a well-known archaeological site in the world. However, an audit of previous research at the site highlighted that most of the knowledge derived from few areas with drystone walling. Consequently, one of the implications of our on-going research engagement with the site is that from time to time, there is need to revisit prominent sites to update understanding based on new theoretical insights afforded by data and by new techniques of investigation. The distribution of material culture at Great Zimbabwe where comparable subsistence, technical and symbolic objects were found across the site, when considered against chronological differences between some of the main components motivates for a new understanding of class relations and inequality at the site. Recourse to African (Shona) philosophy shows that often elites lived with their servants in the same spaces. Consequently, material culture differences are not always a proxy for class differentiation.
Great Zimbabwe had a vibrant production system that took place within homesteads. This is exposed by the fact that remnants of crucibles, slag, and metal objects were through time, found in walled areas and unwalled settlements. Similarly, the local pottery was broadly identical and was characterised by similar shapes suggesting common functions, across the site. Broadly speaking, the cultural, economic and social behaviours represented on the site were the same hinting at strong cultural continuities through time.
However, the bulk of the commoners were resident away from the capital in their own homesteads. Often, these areas were close to resources such as gold mines, salt pans and wild animals. This made networks of circulation very important in sustaining the state. The local circulation system, with distance morphed into regional and long-distance networks. This attracted the circulation of materials from the nearby Indian Ocean such as cowrie and from distant parts of Africa such as metal gongs, and copper ingots. Objects from outside the continent such as glass beads, Islamic ceramics and Chinese porcelain were also part of the same circulation system. Amidst this local, regional and inter-continental outlook, Great Zimbabwe remained a quintessentially African urban space. However, it has similarities with other states elsewhere for example that invested heavily in monumental architecture, but class relations, inequality and production remained uniquely African and local.
Shadreck Chirikure holds a British Academy Global Professorship within the School of Archaeology at Oxford. He is Professor of Archaeology, Director of the Archaeological Materials Laboratory and a former Head of the Department of Archaeology at the University of Cape Town. His research interweaves techniques from hard sciences with those from humanities and social sciences to explore ancient African technologies and political economies of precolonial state and non-state systems. Chirikure’s works draw interpretive flavors from African philosophies to revise concepts and to disrupt hegemonic thinking about the evolution of African technologies, their role in society, and to spur a critical reflection, over the long durée of Africa’s place in the world, and the world’s place in Africa. Among others, Chirikure is a past recipient of the Association of Commonwealth Universities Fellowship at Linacre College, Oxford and is a former Mandela-Harvard Fellow. Chirikure is a past recipient of National Research Foundation of South Africa’s Presidential Award for outstanding research by persons under the age of 40 and is a founding member of the South African Young Academy of Science. He is the Editor-in-Chief of the Oxford Research Encyclopedia of African Archaeology, a Senior Editor of the Oxford Research Encyclopedia of Anthropology. In addition, he is one of the co-editors of Cambridge University Press’ History of Technology book series. Chirikure is a member of the Board of Governors for the Arts Council of African Studies Association and is a member of the Society for American Archaeologists Book Award Committee. Shadreck was recently elected to the Advisory Council of the New York based Wenner Gren Foundation for Anthropological Research. He sits on at least nine editorial boards of journals in the archaeology field and cognate disciplines. Chirikure has contributed to a number of art exhibitions, documentaries, radio shows and TV programs aimed at communicating archaeology to the general public.