This study of Civil War-era politics explores how German immigrants influenced the rise and fall of white Americans' commitment to African Americans' rights. Intertwining developments in Europe and North America, Alison Clark Efford describes how the presence of naturalized citizens affected the status of formerly enslaved people and identifies 1870 as a crucial turning point. That year, the Franco-Prussian War prompted German immigrants to reevaluate the liberal nationalism underpinning African-American suffrage. Throughout the period, the newcomers' approach to race, ethnicity, gender, and economics shaped American citizenship law.