Sumter, Thomas,1734–1832, American Revolutionary officer, b. near Charlottesville, Va. He served with Edward Braddock (1755) and John Forbes (1758) in their expeditions against Fort Duquesne in the French and Indian War, and later he fought against the Cherokee. He settled (1765) in South Carolina. Like Francis Marion, he formed (1780) a guerrilla band in the Revolution and harassed the British in the Carolinas. He and the British leader, Banastre Tarleton, struck at each other through 1780. The "gamecock of the Revolution," as Sumter was called, was successful at Hanging Rock, barely escaped with his life at Fishing Creek, was repulsed in a raid on the British post at Rocky Mount, but won again at Blackstock. After the war, he was U.S. Representative (1789–93, 1797–1801), Senator (1801–10), and minister to Brazil (1810–11). Fort Sumter in Charleston harbor is named for him.
See biographies by A. K. Gregorie (1931) and R. D. Bass (1961).