The concept of “Bantu” constitutes one of the most important analytical frameworks for the study of the linguistic and cultural history of sub-Saharan Africa. Introduced in the nineteenth century by European linguists to classify a vast group of related languages, the term was gradually extended to refer not only to a linguistic family but also to populations and cultures. In the African Great Lakes region, this classification has generated debates about the origin of social groups such as the Hutu and the Tutsi. This article examines the linguistic foundations of the concept of Bantu, the historical dynamics of the Bantu expansion, and scholarly controversies surrounding the origin of the Tutsi. Drawing on the works of Vansina, Chrétien, Newbury, and Mamdani, the study shows that the colonial period significantly contributed to the transformation of flexible social categories into rigid ethnic identities. The article argues that Hutu and Tutsi identities should be understood as complex historical constructions resulting from long-term economic, political, and cultural interactions.