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Answer: The Wade-Davis Reconstruction Bill would also have abolished slavery, but it required that 50 percent of a state's White males take a loyalty oath to the United States (and swear they had never assisted the Confederacy) to be readmitted to the Union. Only after taking this "Ironclad Oath" would they be able to participate in conventions to write new state constitutions.
Explanation: After Lincoln’s assassination in April 1865, however, Congress had the upper hand in shaping federal policy toward the defeated South and imposed the harsher reconstruction requirements first advocated in the Wade-Davis Bill.