Ali had been stripped of his world Heavyweight title by boxing's governing bodies after expressing his views on the Vietnam war in 1967. Jimmy Ellis, a friend and stablemate of Ali, then picked up the vacant world title, and retained it until 1970, when he lost it to Frazier. Frazier was then thought to be, in Ali's abscence, the best Heavyweight of the day by many boxing fans. When Ali was allowed to come back, the first fight between these two boxers was agreed upon almost immediately.
The fight took on a circus-like atmosphere: Many boxing fans around the world argued that Ali's speed and ability would blind Frazier, while othrs supported the idea of Frazier beating Ali based on the fact Frazier was known for his power punching and that Ali had been away from competition for so long. On the days leading to the fight, Ali would sneak out to Frazier's training camp and call him an Uncle Sam and he even went as far as saying that Frazier was the White man's champion. All of this angered Frazier. On the night of the fight, there were riots at many United States cities, including Chicago, where a whole theater was almost thrown apart by angry attenders who had just learned they wouldn't be able to watch the fight at that theater.
At Madison Square Garden, where the fight was held, there was policemen on hand. Reporters from all over the world were working that night, and many famous people were at ringside. Woody Allen was seen sitting very close to the ring, and Frank Sinatra was working as a photographer for a very famous magazine. Artist Leroy Neiman made one of his first arts there: He painted Ali and Frazier as they fought.
Frazier and Ali boxed evenly for the first ten rounds, but in round eleven, Frazier came on and hit Ali hard. Ali tried to come back in the next three rounds, but at the end of round 14, Frazier held a lead on the scorecards. With about a minute to go in round 15, Frazier landed a right cross to Ali's chin and Ali went down, cementing Frazier's lead on the scorecards. While Ali got up and finished the bout on his feet, a little later, he had been declared the loser for the first time in his professional boxing career, as Frazier had kept the world Heavyweight title by a 15 round unanimous decision.
Ali and Frazier fought twice more, and Ali won both of their two other fights, including the Thrilla in Manila. While many boxing fans consider The Thrilla in Manila to be the greatest fight of all time, others argue that the Fight of the Century deserves that title more.
Both boxers are in the International Boxing Hall of Fame nowadays.