Charles Sumner (1811-74), a Senator from Massachusetts for more than twenty years (1851-74), was the leader of the Radical Republicans in the Senate and a lifelong proponent of social equality for blacks. He also supported prison reform and educational reforms.
Sumner's 1856 antislavery speech in the Senate assailed both the Kansas-Nebraska Act of 1854 and the southern representatives who supported it. In one of the most shocking incidents in American history, Sumner was consequently attacked on the Senate floor and beaten with a cane by South Carolinian Preston Brooks, whose uncle was one of the men Sumner had criticized. It took Sumner more than three years to recover from the assault, a display of violence which galvanized the North. After his return, Sumner strongly supported Lincoln's Emancipation Proclamation, and claimed that the Confederate states had "committed suicide" by seceding, thereby forfeiting their constitutional rights. Together with Thaddeus Stevens in the House, Sumner led the fight for the Congressional (or "Radical") Reconstruction program that sought to ensure liberty and equality for blacks and enfranchisement for black men. He also led the movement to impeach Andrew Johnson. Sumner's relationship with the next president, Ulysses S. Grant, deteriorated over Grant's notion to annex Santo Domingo. Sumner was subsequently removed from his chairmanship of the committee on foreign relations. Two years after helping organize the short-lived Liberal Republican party in 1872, he suffered a fatal heart attack.