You were old enough for junior high history, right?
Compromise of 1877 ended Reconstruction and the Republicans abandoned African-Americans in the South for the Presidency (Hayes) in exchange the Democrats received withdrawal of federal troops from the Confederate states. As federal troops left, Republicans returned to the North and Redeemer/Lost Cause Democrats filled the void and the Jim Crow/Son of Ham legal structure prevailed.
African-Americans would suffered for 90+ years until federal action was finally taken against the South.
It was a horrific mistake and should surprise no one.