Collectivism and new identities after the Black Death Pandemic: Merchant diasporas and incorporative local communities in West Africa

•Two waves of population loss are identified contemporary with Black Death pandemic.•Transformations occurred in politics, religion, identities, economy, and environment.•New commercial goods and material culture suggest arrival of Mande diaspora.•Merchant diasporas expanded in cooperation with local communities after pandemic. Merchant diasporas have significantly influenced local and interregional processes in world history, but archaeology is only starting to understand the diversity of political, economic, social and religious contexts within which they developed. Recent research has suggested that the second plague pandemic (Black Death) likely affected West Africa. However, little is known regarding the diversity of local and regional impacts and responses. We argue that documented population losses likely caused by plague resulted in disruptions to commercial networks and stimulated merchant diasporas from neighboring Mali into Burkina Faso and further south. Drawing on an expanded corpus of data and new stratigraphic and Bayesian analyses of AMS dates from the site of Kirikongo (western Burkina Faso), this paper identifies two waves of likely plague-related depopulation in the fourteenth and early fifteenth centuries AD and explores the resulting social, economic, religious and environmental transformations. Notably, local communities worked cooperatively with recently arrived Mande merchant diasporas from the Empire of Mali to reconstruct regional economies.