By 1860, 1,748 slaves of African descent were in the county, generally brought in from the South by slaveholder migrants. In 1861, the people of the county voted 314–22 in favor of secession from the Union. Guadalupe County sent several troops to fight for the Confederate States Army. Following the end of the Civil War and the emancipation of the slaves (1865), a Freedmen's Bureau office opened in 1866 in Seguin to supervise work contracts between former slaves and area farmers. Together, German Americans and African Americans joined the Republican Party, leading Guadalupe County to be a reliably Republican one into the 20th century, even after the state disfranchisement of African Americans in 1901 by imposition of a poll tax.