Cassius Marcellus Clay may refer to:
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Cassius Marcellus Clay (politician)
Major-General Cassius Marcellus Clay (October 19, 1810 – July 22, 1903) was an American planter, politician, military officer and abolitionist who served as the United States ambassador to Russia from 1863 to 1869. Born in Kentucky to a wealt ...
(1810–1903), American politician and abolitionist
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Cassius Marcellus Clay Sr.
Cassius Marcellus Clay (November 11, 1912 – February 8, 1990) was an American painter and musician. He was the father of three-time World Heavyweight Champion Muhammad Ali and Rahman Ali, and the paternal grandfather o ...
(1912–1990), American painter and musician, named after the abolitionist, father of the boxer
*Cassius Marcellus Clay Jr. or
Muhammad Ali
Muhammad Ali (; born Cassius Marcellus Clay Jr.; January 17, 1942 – June 3, 2016) was an American professional boxer and activist. Nicknamed "The Greatest", he is regarded as one of the most significant sports figures of the 20th century, a ...
(1942–2016), American boxer
{{hndis, Clay, Cassius Marcellus