Reconstruction Era Civil Rights Statutes
In the wake of the Union victory in 1865 over the traitorous white South, the expectation of those who had fought to defend slavery was that the federal government would impose a radically new order. Instead, President Andrew Johnson made clear his intention to permit the white power structure to reassert itself at the expense of African-Americans. Many states passed Black Codes intended to deprive African-Americans of the right to labor freely, and a reign of terror began.
In response, Radical Republicans in Congress led efforts to secure equal rights for African-Americans. This battlefield was in part constitutional, culminating in the passage of the Fourteenth and Fifteenth Amendments (the Thirteenth Amendment, abolishing slavery, had already been passed by Congress and ratified by a sufficient number of states in 1865).
The fight was also legislative, and, in the period from 1866 to 1875, a series of enactments placed the force of federal law squarely on the side of civil rights enforcement.