Muhammad Ali with his winnings, 1974 Muhammad Ali born Cassius Marcellus Clay Jr. January 17, 1942 - June 3, 2016) was an American professional boxer, activist, and philanthropist. He is much regarded as one of the most significant and celebrated sports figures of the 20th century. From early in his career, Ali was known as an inspiring, controversial, and polarizing figure both inside and outside the ring. He was born and raised in Louisville, Kentucky, and began training as an amateur boxer when he was 12 years old. At age 18, he won a gold medal in the light heavyweight division at the 1960 Summer Olympics in Rome and turned professional later that year. At age 22 in 1964, he won the WBA, WBC, and lineal heavyweight titles from Sonny Liston in a major upset. He then announced his conversion to Islam and changed his name from Cassius Clay, which he called his "slave name", to Muhammad Ali. He sets an example of racial pride for African Americans and resistance to white d...