Conflict and violence are an integral part of human nature. As an essential part of African personhood and social/historical experience, they played a significant role in political development and demographic configuration in pre-colonial African cities and states. This paper focuses on the place of conflict and violence in the demographic configuration or composition in Southwestern Nigeria, drawing mainly on data from the Yoruba areas of Nigeria. The paper shows that in both the short and long terms, the warfare and power politics of Yorubaland in the nineteenth century affected the configuration not only among the rather well-known Yoruba sub-groups, but also among nearby non-Yoruba coastal and hinterland communities, with varying degrees of social, economic and political effects.