Sumner, Charles (1811–1874), a United States statesman. For nearly 25 years he served as United States senator from Massachusetts, 1851–74. Sumner was brilliant, vain, unyielding, and often vituperative, but was regarded as a man of courage and integrity. He was an implacable foe of slavery and used his oratorical skills to denounce the institution and its supporters. A speech he delivered in 1856 attacking the Kansas-Nebraska Act so enraged Representative Preston S. Brooks of South Carolina that he beat Sumner with a cane. Sumner was unable to resume his duties for three years.

Sumner, who had entered the Senate as a candidate of Free Soilers and Democrats, helped to organize the Republican party and became its Senate leader when it gained power in 1861. During the Civil War, he headed the Senate foreign relations committee and played an important role in preventing European intervention in the conflict. After the war, Sumner fought for increased political and social rights for the former slaves. With Thaddeus Stevens, he sought enactment of the Radical Republican reconstruction program for the defeated South and strongly supported the impeachment of President Johnson. During the Grant administration, he was generally at odds with the President's policies, which led him to join the Liberal Republican party.

Sumner was born in Boston. He graduated from Harvard, 1830, and Harvard Law School, 1834, and practiced law before entering the Senate.