Radical Reconstruction imposed military occupation in the South and required new state constitutions guaranteeing voting rights for all men. The Radical Republicans who controlled Congress tried to limit President Johnson's power by passing the Tenure of Office Act and impeaching him when he fired Secretary of War Edwin Stanton, though he was acquitted by one vote. Freedmen's bureaus provided aid to former slaves, while the 13th, 14th, and 15th Amendments abolished slavery and guaranteed citizenship and voting rights in an attempt to integrate freed slaves into society.