During Reconstruction, the South was under occupation by federal forces, and Southern state governments were dominated by Republicans, elected largely by freedmen and allies. Republicans nationally pressed for the granting of political rights to the newly-freed slaves as the key to their becoming full citizens and the votes they would cast for the party. The Thirteenth Amendment (banning slavery), Fourteenth Amendment (guaranteeing the civil rights of former slaves and ensuring equal protection of the laws), and Fifteenth Amendment (prohibiting the denial of the right to vote on grounds of race, color, or previous condition of servitude), enshrined such political rights in the Constitution.