During the Civil War, President Lincoln began formulating a plan to reunify the nation when the war came to an end. He felt reunification should be a gentle and gradual process. He planned to pardon Confederates who severed their Confederate ties and took an oath to uphold the US Constitution and the Union. When 10% of the people who had voted in 1860 in each state had taken the oath, and when their legislature had abolished slavery, then the state could be readmitted to the Union.
This plan was countered in 1864 by Radical Republicans in Congress who thought it too lenient. They proposed the Wade-Davis Bill which said that half the male voters had to take the oath and repudiate having voluntarily been a Confederate, and the legislature had to abolish slavery. Lincoln vetoed the bill, saying it was too harsh.
When Lincoln was killed on April 14, 1865 and Andrew Johnson, who was a pro Union Democrat from Tennessee, became president, he followed in the more lenient direction. He recognized the states that had reorganized themselves under Lincoln’s plan and required the remaining southern states to disavow their secession, repudiate their war debts, and ratify the thirteenth amendment which abolished slavery. However, when many states did not fulfill these requirements, sent many wartime leaders to Congress, and did not give freedmen their rights, he recognized the new governments anyway.
This set the stage for both the moderate and radical Republican members of Congress to set forth their own plan. They did not want Confederates to be forgiven for their acts, opposed the Black Codes that southern legislatures had passed, and wrote the Reconstruction Act of 1867. It barred Confederates as office holders and set up military governments in states until they were readmitted into the Union. In 1866, they passed the Fourteenth Amendment, which gave citizenship to African Americans, and the Fifteenth Amendment in 1870, which gave all male citizens the right to vote. They also strengthened the Freedmen’s Bureau which had been established in 1865 to help former slaves. By 1871, with the help of newly enfranchised African American voters, all the state legislatures in the south had fulfilled the requirements and were readmitted into the Union.
Basically, the strength of Johnson’s plan was that the South could be eased back into the Union. Its weakness was that Black Codes kept African Americans in conditions of servitude.
The strengths of Radical Reconstruction were that it passed the 13th, 14th and 15th Amendments. Its weakness is that the gains could not last. The southern economy was in a shambles, poor white and black citizens often became sharecroppers, and resentment led to terrorism, Jim Crow laws, and the Ku Klux Kan.