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α: calibrated so average coauthorship-adjusted count equals average raw count
This paper studies the role of leaders in the social movement against slavery that culminated in the US Civil War. Our analysis is organized around a natural experiment: leaders of the failed German revolution of 1848–1849 were expelled to the United States and became antislavery campaigners who helped mobilize Union Army volunteers. Towns where Forty-Eighters settled show two-thirds higher Union Army enlistments. Their influence worked through local newspapers and social clubs. Going beyond enlistment decisions, Forty-Eighters reduced their companies' desertion rate during the war. In the long run, Forty-Eighter towns were more likely to form a local chapter of the NAACP.