Muhammad Ali, legendary boxer and civil rights activist, passed away on Friday June 3 in a Phoenix-area hospital where he was being treated for respiratory issues, NBC News confirms. The three-time World Heavyweight Champion was 74.

Ali had been suffering from Parkinson's disease for over 32 years, Bob Gunnell, a spokesman for the Ali family, told NBC. A funeral service is reportedly planned to take place in his hometown of Louisville, Kentucky.

The man known as "The Greatest of All Time" was originally born Cassius Marcellus Clay on January 17, 1942 in Louisville. He started boxing when he was only 12, winning a number of Golden Gloves titles before triumphing at the 1960 Olympics in Rome, where he took home a gold medal.

No stranger to controversy throughout his prolific lifetime, at the age of 22 he renounced his "slave name," Cassius, and changed it to Muhammad Ali, bestowed upon him by the Nation of Islam — an American Muslim sect, led in part by human rights activist Malcolm X.

In 1967, he was drafted to serve in the U.S. Army to fight in the Vietnam Way. He refused to serve, maintaining that the war conflicted with his religious beliefs, a stance that resulted in his titles being stripped and a conviction for draft evasion. In 1971, after his appeal reached the U.S. Supreme Court, his conviction was reversed.

After retiring for good in 1980, Ali threw himself into global humanitarian work throughout the '80s and '90s, and in 2005, he was honored by President George W. Bush with the Presidential Medal of Freedom.

He is survived by nine children, and will be remembered for his momentous impacts on sports, culture, and human rights across the world.

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