Muhammad Ali (17 January 1942 - 3 June 2016) was an American professional boxer, activist, entertainer, poet and philanthropist. He is widely regarded as one of the most significant and celebrated sports figures of the 20th century.

Ali was born Cassius Marcellus Clay Jr in Louisville, Kentucky. He became a Muslim in 1961 and on 6 March 1964, he announced that he no longer would be known as Cassius Clay but as Muhammad Ali.

Cassius Clay began training as an amateur boxer at age 12. At 18, he won a gold medal in the light heavyweight division at the 1960 Summer Olympics and turned professional later that year. He won the world heavyweight championship from Sonny Liston in a major upset on 25 February 1964, at age 22.

In 1966, Muhammad Ali refused to be drafted into the military, citing his religious beliefs and ethical opposition to the Vietnam War. He was found guilty of draft evasion and faced 5 years in prison. He stayed out of prison as he appealed the decision to the Supreme Court, which overturned his conviction in 1971. Ali's actions as a conscientious objector to the Vietnam War made him an icon for the larger counterculture generation. and he was a very high-profile figure of racial pride for African Americans during the civil rights movement and throughout his career.

During his career Ali fought in several historic boxing matches and is frequently ranked as the greatest heavyweight boxer of all time.

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