Earthwork Landscapes Of Protection And Regulation: Chronology, Construction, And Meaning At Sungbo’s Eredo, Africa’s Largest Known Structure

This dissertation investigates questions of when, how, and why the 2nd millennium AD earthwork structure of Sungbo’s Eredo, southwestern Nigeria, was constructed and utilized by past Ijebu-Yoruba communities. To address these questions, the research combines archaeological excavations of the Eredo, as well as settlement sites adjacent to it, surveys of associated local shrines, and investigation of colonial and later archives relating to the earthwork landscape. Excavations and surveys primarily occurred at the sites of Augustine University and Eredo Village, Lagos State, Nigeria, while archival work largely drew upon both colonial British archives as well as the papers of 20th century scholars who worked in the Ijebu region. The research has contributed several new insights into the dates, construction, functionality and meaning of Sungbo’s Eredo. Novel chronological evidence suggests that it was constructed around the 15th century AD and continued to be relevant to local communities throughout the 15th to 21st centuries in multiple evolving ways. New stratigraphic evidence from the earthwork, cross-referenced with similar evidence from other sites along it, and a range of Modern and Early Modern accounts, is interpreted as suggesting a segmented process of construction by which local groups – coordinated by centralised authorities and specialised institutions – mobilised labour to construct their own portions of the earthwork according to their own knowledge and practices. Novel artefactual, survey, and archival evidence suggests that the earthwork performed a variety of evolving functions. Broadly, these pertained to physical and spiritual protection of communities within, regulation of persons, things, and entities seeking to enter and exit the enclosed territory, demarcation and consolidation of emergent hierarchies and subordinate populations, and maintenance of secrecy and isolation. The earthwork has also held an evolving mnemonic importance to communities over the centuries, with developing narratives pertaining to its legendary builder – Sungbo – and a host of other entities memorialised and sacralised by it, shaping community existence and reality as the world changed around them. The dissertation thus concludes, and further underlines, that linear earthwork structures in West Africa were multifunctional structures with many uses and meanings coexisting and changing over time, highly complex architectural constructs involving diverse knowledge and decision-making (and not simple accumulations of earth), and forms of monumental architecture central to local concepts of being in the world.