John Williams (January 29, 1778 – August 10, 1837) was an American lawyer, soldier, and statesman, operating primarily out of Knoxville, Tennessee, in the first part of the 19th century. He represented Tennessee in the United States Senate from 1815 to 1823, when he lost reelection to Andrew Jackson. Williams also served as colonel of the 39th U.S. Infantry Regiment during the Creek Wars, and played a key role in Jackson's victory at the Battle of Horseshoe Bend in 1814.