Muhammad Ali openly called himself The Greatest and backed that up by being the first boxer to win the heavyweight title three times. Ali won his first title as Cassius Clay (his real birth name) in 1964 by beating Sonny Liston. However, shortly after the fight, he became a Muslim and changed his name to Muhammad Ali because he believed that Cassius Clay was his “slave name.” In 1967 Ali was stripped of his title because he refused to join the US Army because of his religious beliefs. That wasn’t enough to keep him down though, when he regained the title in 1974 by defeating George Foreman in Zaire’s famous Rumble in the Jungle. He also got the title again in ’78 after he beat Leon Spinks. Ali retired in 1981 and now raises money and awareness for Parkinson’s Disease, that he suffers from.