Reconstruction

According to Ginsberg, Lowi, and Weir:

Protected by the presence of federal troops, African American men were able to exercise their political rights immediately after the [Civil] war. During Reconstruction, blacks were elected to many political offices: two black senators were elected from Mississippi and a total of fourteen African Americans were elected to the House of Representatives between 1869 and 1877. African Americans held many state-level political offices. As voters and public officials, black citizens found a home in the Republican Party, which had secured the ratification of the three constitutional amendments guaranteeing black rights. ... This political equality was short-lived, however. The national government withdrew its troops from the South and turned its back on African Americans in 1877. In the Compromise of 1877, southern Democrats agreed to allow the Republican candidate, Rutherford B. Hayes, to become president after a disputed election. In exchange, northern Republicans dropped their support for the civil liberties and political participation of African Americans (pages 161-62).