How did the south reverse much of the civil rights act of 1866?

ANSWER:

With the pass of the black codes the South reversed much of the Civil Rights Act of 1866.

EXPLANATION:

Black Codes were a part of a bigger example of the Southern whites attempting to keep up political dominance and repress the freedmen, recently liberated African-American slaves. Black codes basically changed for "slave codes" in those states. Prior to the war, a few states that had banned slavery again instituted Black Codes.