William L. Marcy (born Dec. 12, 1786, Southbridge, Mass., U.S.—died July 4, 1857, Ballston Spa, N.Y.) was a U.S. politician, governor, and Cabinet member, remembered primarily for his remark: “To the victor belong the spoils of the enemy.”
From 1823 to 1829 Marcy was comptroller of New York state and a leading member of the “Albany Regency,” a group of powerful Democrats. After serving as an associate justice of the New York Supreme Court (1829–31), he entered the U.S. Senate, where, in a speech defending Secretary of State Martin Van Buren against an attack by Sen. Henry Clay, he made his remark and thereby became known as champion of the “spoils system.” He resigned from the Senate (January 1833) to become governor of New York (1833–39). Marcy was secretary of war under Pres. James K. Polk (1845–49) and secretary of state under Pres. Franklin Pierce (1853–57).
In the latter office he secured approval of the Gadsden Treaty (1853), which settled the boundary dispute between Mexico and the United States; he also settled the Black Warrior case (1854), thus avoiding war with Spain.