"Radical Republicans" were a faction within the Republican Party during and after the Civil War that advocated for extreme measures against the South and sought to ensure civil rights for freed slaves.

They supported immediate emancipation and believed in a strict Reconstruction policy that would impose significant changes in Southern society and government. This group aimed to protect the rights of African Americans and punish Southern leaders for their role in the rebellion. Key figures included Thaddeus Stevens and Charles Sumner, who played vital roles in shaping legislation during this transformative period in American history.