A large body of research has shown that American politics have been highly influenced by conservative movements born in American White suburbia. Yet, suburbs are also moving left and becoming more diversified. I argue that this context has led to new cityhood movements in unincorporated areas of some regions of the US. By forming cities, unincorporated communities detach themselves from shared county-level authorities and the wider populations served in these jurisdictions. What triggers municipal incorporations today and how are recent incorporation movements different from those of the postwar era? To answer these questions, I conduct fieldwork in Georgia. I find that municipal incorporations are a modern type of segregation triggered by sentiments of racial threat and conservatism, which I call White fortressing. I update the study of government formation by analyzing a new wave of municipal incorporations and contribute to the literature works on White flight, racial threat, and residential segregation.