The article focuses on the historical causes and effects of the social, economic and demographic divisions of the two communities, Macedonians and Albanians, which constitute two very distinct societies put together into one state, and do not form an integrated polity. This deep gulf is caused by significant differences in the structures of communal life, reproductive and economic behavior, and patterns of cultural reproduction. The differences have been mainly created by the social and economic effects of Macedonian nation-building and socialist modernization whose outcomes varied on the two ethnic groups.