'The Barbarism of Slavery' is a speech delivered by Charles Sumner, an American statesman and United States Senator from Massachusetts, on the Bill for the Admission of Kansas as a Free State. Sumner was the leader of the anti-slavery forces in the state and a leader of the Radical Republicans in the U.S. Senate during the American Civil War. South Carolina Democratic congressman Preston Brooks once beat Sumner nearly to death with a cane on the Senate floor after Sumner delivered an anti-slavery speech, “The Crime Against Kansas.”