The Republicans feared that there could be a re-enslavement of the blacks. Therefore, in return, the Republicans in Congress then moved to pass the Wade-Davis Bill in 1864. This bill required that 50 percent of the South would have to take an oath of allegiance and demanded stronger safeguards for emancipation than Lincoln's as the price of readmission. The Wade-Davis Bill was pocket-vetoed by Lincoln who was assassinated shortly after.
Moderate Republicans agreed with Lincoln's ideals. They believed that the seceded states should be restored to the Union swiftly and on terms of Congress, not the President. They also favored the use of federal power to alter the Southern economic system. Radical Republicans, comprised of Northern politicians, were strongly opposed to slavery, unsympathetic to the South, wanted to protect newly free slaves, and keep their majority in Congress. The radicals wanted to social structure of the South to be change before it was restored to the Union. They wanted the planters punished and the blacks protected by federal power. Radical Republicans were against Abraham Lincoln. .
Besides putting the South under the rule of federal soldiers, the Military Reconstruction Act of 1867 required that Southern states to give blacks the vote as a condition of readmittance to the Union. It provided certain functions and strict regime under the presidency. The case of Ex parte Milligan stated that a citizen not connected with the military service and a resident in a State where the courts are open and in their jurisdiction cannot, be tried, convicted, or sentenced otherwise than by the ordinary courts of law. .
Now, after the war ended, the 13th Amendment was passed to freed the slaves. Black Codes was established to provide economic assistance to get former slaves started as sharecroppers. They were aimed to ensure a stable labor supply and they sought to restore the pre-freedom system of racial relations.