The Radical Republicans took several different steps to make Reconstruction harder for the white South including:
1) Development of the Freedmen's Bureau- This federal agency was made to ensure that African-American citizens were having their constitutional rights protected. This meant that white Southerners could not enslave these individuals anymore.
2) Reconstruction Acts- These laws helped to organize the former Confederacy into different military zones that were monitored by the federal government.
3) Constitutional Amendments- Radical republicans allowed African-American men the right to vote and outlawed slavery in its entirety, breaking down the oppressive system set up by white Southerners.