Through the late 19th century, whites worked to re-establish supremacy after Reconstruction and impose Jim Crow and second-class status on African Americans. Tennessee effectively disenfranchised most blacks in the state after the turn of the 20th century, excluding them from the political system and destroying what had been a competitive system. The state's congressional delegation and elected officials became predominantly white Democrats. The exception was East Tennessee, where white Republicans formed the majority. The region of yeomen farmers had been mostly Unionist-leaning during the Civil War.