Setting the scene
Cassius Marcellus Clay Jr. was born on January 17, 1942, in Louisville, Kentucky. A stolen bicycle led twelve-year-old Cassius to a boxing gym, where coach Joe Martin taught him to fight.
What happened
Clay won Olympic gold in Rome in 1960, then upset Sonny Liston for the heavyweight title in 1964, announcing his conversion to Islam and name Muhammad Ali. He refused induction into the Vietnam draft in 1967, losing his title and facing prison before the Supreme Court reversed his conviction.
Why it still matters
Ali regained the championship twice, fought Joe Frazier and George Foreman in legendary bouts, and lit the 1996 Atlanta Olympic cauldron trembling from Parkinson's. Memorable detail: before the 1974 'Rumble in the Jungle' in Zaire, Ali coined 'rope-a-dope' to let Foreman tire himself punching Ali's guard against the ropes.
Background
Olympic gold and heavyweight titles followed.