John Hemphill is the name of: John Hemphill (U.S. Senator) (1803–1862), U.S. Senator from Texas and Chief Justice of the Texas Supreme Court John Hemphill (comedian) (born 1966), American comedian John Hemphill (actor), Canadian actor in Maniac Mansion and Schitt's Creek and comedy writer who appeared in Second City Television John J. Hemphill (1849–1912), U.S. Representative from South Carolina