(born Oct. 9, 1782, Exeter, N.H., U.S.—died June 17, 1866, Detroit, Mich.) U.S. politician. He fought in the War of 1812 and served as governor of Michigan Territory (1813–31). As secretary of war (1831–36) under Pres. Andrew Jackson, he directed the conduct of the Black Hawk and Seminole wars. He served as U.S. minister to France (1836–42). In the U.S. Senate (1845–48, 1849–57), he supported westward expansion and the Compromise of 1850. He was the Democratic nominee in the presidential election of 1848, which he lost to Zachary Taylor. He later served as secretary of state (1857–60) but resigned when Pres. James Buchanan took no action to counter the secession of the Southern states.
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