Muhammad Ali was one of America's greatest 20th century boxers and athletes. Muhammad Ali was born Cassius Clay in Louisville, Kentucky. He started fighting at the age of 12 after his bicycle was stolen. Under the guidance of Joe Martin, Clay became an explosive boxer and won six Kentucky Gold Gloves during high school. In 1960, Clay won a gold medal in the Olympics at Rome, Italy.

Clay then turned professional under the guidance of Angelo Dundee and became famous for his unorthodox style. Ali tirelessly promoted himself and earned the nickname "The Louisville Lip" for statements such as "I am the Greatest," and "I'm young, I'm pretty, I'm fast, and no one can beat me." From 1960-1963, Cassius Clay was 19-0 with 15 knockouts. On February 25, 1964, Clay defeated Sonny Liston and won the World Heavyweight Championship.

In 1965, Clay joined the Nation of Islam and changed his name to Muhammad Ali. Ali defended his championship for the next several years, winning many matches with a breathtaking combination of speed and power. In 1967, however Ali was stripped of his championship for refusing to fight in the Vietnam War. Ali immediately became a controversial figure, and was the subject of outrage for many Americans. Although Ali lost his title to Joe Frazier in 1971, he cemented his title as "The Greatest" by outdueling George Foreman in 1974 in "The Rumble in the Jungle". In 1975, Ali defeated Joe Frazier in "The Thrilla in Manila". In one of the best fights in boxing history, Ali won by TKO after the 14th round. In 1981, Ali retired with a career record of 56-5, with 37 knockouts. Ali remains a hero to millions of people throughout the world. In 1982, he was diagnosed with Parkinson's Disease. Today, his daughter, Laila Ali, is a prominent female boxer.