Black Out-Migration and Southern Political Realignment

Can emigration from less democratic and economically less developed areas induce political and economic change? We study this question in the context of the second Great Migration of African Americans (1940–1970), when more than 4 million blacks left the U.S. South and moved to the urban North. To deal with the endogeneity of black emigration, we construct a “reversed” shift-share instrument which predicts black outflows by interacting pre-determined shares of blacks born in southern counties and living in the North with observed migration flows into northern areas. Using this empirical strategy and relying on a variety of datasets assembled and digitized from historical archives, we find that black emigration reduced support for segregationist candidates in Presidential and in Democratic primary elections, and increased the share of county resources devoted to black schools. Our interpretation is that black emigration was economically costly for the white elites who reacted by making political concessions to limit the outflow of African Americans. Consistent with the idea that black departures increased labor costs in agriculture, we find that the Great Migration reduced the prevalence of tenancy and lead to farm consolidation. We conclude by documenting that the effects of black emigration on mechanization and on farm value were highly heterogeneous, and depended crucially on initial farm size.