Ironclad oath

The Ironclad Oath was an oath promoted by Radical Republicans and opposed by President Abraham Lincoln. By requiring officials and voters to swear they had never supported the Confederacy, it limited the political activity of ex-Confederate soldiers and supporters. It enabled a Republican coalition to come to power in ten Southern states during Reconstruction, and was the source of anger on the part of local civic leaders who were prevented from voting or holding office.

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