Fred Mustard Stewart (September 17, 1932, Anderson, Indiana – February 7, 2007, New York City) was an American novelist.
His most popular books were The Mephisto Waltz (1969), adapted for a 1971 film starring Alan Alda; Six Weeks (1976), made into a 1982 film starring Mary Tyler Moore; Century, a New York Times best-seller in 1981; and Ellis Island (1983), which became a CBS mini-series in 1984.
Stewart attended The Lawrenceville School in New Jersey, class of 1950.
He graduated from Princeton University in 1954, where he was a member of the Colonial Club.
He originally planned to be a concert pianist, and studied with Eduard Steuermann at the Juilliard School.