jan 1, 1866 - Civil Rights Act of 1866
This act did not let the Southern states enact racist black codes that would take away any rights of the African Americans in the South. This meant that some of the black codes could still be of use if it did not limit the social and economic rights of the black population. This eventually lead to the 14th Amendment that gave them even more rights as people living in the United States.
Added to timeline:
Causes after the Civil War with descriptions