The most famous leaders during the Reconstruction era were Senators Thaddeus Stevens of Pennsylvania and Charles Sumner of Massachusetts. Both were leaders of the Radical Republicans who were determined to remake the South as a mirror image of the North. Although Lincoln had hoped to bring the Southern states back into the Union on lenient terms, Stevens said that the Southern states had reverted to the state of "conquered provinces." Sumner said that they had committed political suicide, and thus had reverted to the status of unorganized territories. In either event, they were subject to the absolute will of Congress. Andrew Johnson's role was minor at best. Originally, he said the Southern states had never left the Union, so reconstruction was unnecessary. He vetoed almost all Reconstruction bills, but the vetoes were easily overridden. He fell into the Impeachment trap by firing Edwin Stanton as Secretary of War, and although he was not removed from office, was virtually ineffective thereafter.
There were a number of leaders who were involved in the various phases of Reconstruction.
The most famous of the leaders were the presidents who ran the country during the Reconstruction Era. President Lincoln was involved in the very first phases of Reconstruction as he was president as the war ended. He had already laid out a plan for Reconstruction but did not live to implement it. Pres. Johnson was the other president closely involved in Reconstruction. He tried to carry out his own, relatively lenient plan.
Johnson's efforts were rejected by the Radical Republicans who then took over Reconstruction during the time known as Radical Reconstruction (or Congressional Reconstruction). The best known of their leaders were people like Thaddeus Stevens and Charles Sumner.
These men are the most prominent leaders involved in the Reconstruction Era.