William Trousdale (September 23, 1790March 27, 1872) was an American soldier and politician. He served as Governor of Tennessee from 1849 to 1851, and was United States Minister to Brazil from 1853 to 1857. He fought under Andrew Jackson in the Creek War, the War of 1812 and the Second Seminole War, and commanded the U.S. Fourteenth Infantry in the Mexican-American War. His military exploits earned him the nickname, "War Horse of Sumner County."