Morris King "Mo" Udall (June 15, 1922 – December 12, 1998) was an American politician who served as a U.S. Representative from Arizona from May 2, 1961 to May 4, 1991. A former professional basketball player with the old National Basketball League Denver Nuggets, noted for his liberal views, Mo Udall was a tall (6'5"), Lincolnesque figure with a self-deprecating wit and easy manner. Because of his wit, columnist James J. Kilpatrick deemed him "too funny to be president", which also ended up being the title of his autobiography in the 1980s. Udall earned a law degree from the University of Arizona in 1949. He was a member of The Church of Jesus Christ of Latter-day Saints.

Udall was born in St. Johns, Apache County, Arizona, a son of Louisa (née Lee) and Levi Stewart Udall. He lost his right eye to a friend's pocket knife at the age of 6, while the two were attempting to cut some string, and wore a glass eye for the rest of his life. He attempted to enlist in the Army early in World War II, and almost succeeded, by covering his glass eye each time he was told to alternate during the eye exam. After he was medically cleared, another potential enlistee complained that he had been medically rejected for flat feet, while Udall had been cleared with a blind eye. This caused the examiners to retest Udall under closer scrutiny, and he was rejected. Later, medical standards changed and Udall served in the Army until the end of the war.