The Genetic Legacy of State Centralization in the Kuba Kingdom of the Democratic Republic of the Congo

Few phenomena have had as profound or long-lasting consequences in human history as the emergence of large-scale centralized states in the place of smaller-scale and more-local societies. This study examines a fundamental, and yet, unexplored consequence of state formation: its genetic legacy. We study the genetic impact of state centralization during the formation of the eminent pre-colonial Kuba Kingdom of the Democratic Republic of the Congo (DRC) in the 17th century. We analyse novel genome-wide data from over 690 individuals sampled from 27 different ethnic groups from the Kasai Central Province of the DRC. By comparing patterns of haplotype sharing in the present-day Kuba, who’s ancestors were part of the Kuba Kingdom, to neighboring non-Kuba groups we show that the Kuba today are more genetically diverse and more similar to other groups in the region than expected, consistent with the historical unification of distinct sub-groups during state centralization. We also find evidence of genetic mixing dating to the time of the Kingdom at its most prominent. Using this unique dataset we characterize the history of the Kasai Central province for the first time and describe the historic late Bantu migrations that brought with it an ancestry component found across large parts of Africa today. Taken together we show the power of genetics to evidence events of socio-political importance, and highlight how DNA can be used to better understand the behaviors of both people and institutions in the past.