Thomas W. Knowlton (22 November 1740 – 16 September 1776) was an American patriot who served in the French and Indian War and was a Colonel during the American Revolution. Knowlton is considered America's first Intelligence professional, and his unit, Knowlton's Rangers, made a significant contribution to intelligence gathering during the early Revolutionary War. Knowlton was killed in action at the Battle of Harlem Heights.