Cassius Marcellus Clay, Sr. (11 November 1912 – 8 February 1990) was the father of three-time World Heavyweight Champion Muhammad Ali (born 1942) and Rudolph Valentino Clay, who is now named Rahman Ali, and also was the grandfather of Muhammad's daughter Laila Ali. He married Odessa Grady Clay (1917 - 1994) in the 1930s and worked as a painter and a musician.
Clay, Sr., painted billboards and signs. He also played the piano. He was always interested in music, received piano lessons, and played the keyboard, writing all kinds of music that he made up. He was named after the 19th century abolitionist and politician Cassius Marcellus Clay.
Clay, Sr., was portrayed by Giancarlo Esposito in the two-time Oscar-nominated film Ali which was released in theatres on 25 December 2001 in the United States and on22 February 2002 in the United Kingdom.
He died on 8 February 1990 after suffering a heart attack while leaving a department store in Jefferson County, Kentucky. He was 77 years old.