Muhammad Ali is known around the world as more than just an athlete. He has become a cultural icon, role model, and humanitarian as his influence has spanned generations. As he celebrates his 70th birthday today, Ali’s legacy has helped him cement his claim of being the “greatest.”

“I feel so proud and honored that we’re able to show our feelings and show our support for him,” said former World Heavyweight Champion Lennox Lewis said. “What he’s done outside the ring, just the bravery, the poise, the feeling, the sacrifice; he’s truly a great man.”

theGrio slideshow: Muhammad Ali’s 10 greatest fights

On Saturday night, Ali was in his hometown of Louisville, Ky. reveling in the cheers, love, and admiration of hundreds of friends and celebrity admirers at the first of five birthday parties scheduled for this month. This celebration was a $1,000-per-person fundraiser at the Muhammad Ali Center in downtown Louisville.

“The reason I loved him is because of his confidence,” said University of Kentucky men’s basketball coach John Calipari. “He would talk and then back it up. He had great courage and who had more fun than him?”

Among the attendees at the party were Sarah Shourd, Shane Bauer, and Joshua Fattal, the three American hikers who were held captive as accused spies in Iran. It was Ali, one of the most prominent American Muslims, who lobbied for their eventual release.

Ali’s humanitarian efforts have matched his effects on American pop culture. From his numerous quips and catchphrases, to his brash, in-your-face openness, to his controversial stances on race, Ali set a tone far different from professional athletes of his era.

theGrio slideshow: Michelle Obama celebrates 48th birthday

“Ali was the primary reason I took up boxing,” said BBC boxing commentator Mike Costello. “I wonder how many more youngsters across the globe pushed open a gym door for the same reason?”

His effect on pop culture remains prominent to this day. He has a star on the Hollywood Walk-of-Fame, has had 30 books written about him, has appeared on the cover of Sports Illustrated 37 times (second to Michael Jordan for most ever), and has been the subject of seven movies (including one in which he played himself), including the Academy Award-winning documentary When We Were Kings.

Ali also appeared in numerous television programs during the ‘70s and ‘80s, had advertising deals with Coca-Cola and Pizza Hut, had his own Saturday morning cartoon — NBC’s The Adventures of Muhammad Ali in 1977, and has been referenced in hundreds of songs. In many ways, he was the original pop icon and set the stage for generations of athletes to market themselves on and off the field.

“He’s still the greatest,” Lewis said. Ali was born Cassius Marcellus Clay on January 17, 1942 in Louisville. He was steered into boxing at age 12 by a Louisville police officer — boxing coach Joe Martin — after his bicycle was stolen. Within six years, Clay had won six Kentucky Golden Gloves titles, two National Golden Gloves titles, an AAU National Title, and the Light Heavyweight gold medal in the 1960 Summer Olympics.

However, when Clay returned to Louisville after winning the gold medal, he was refused service in a “whites-only” restaurant. According to his autobiography, after a fight with an all-white gang, he angrily threw the gold medal in the Ohio River (it was eventually replaced in 1996).

After winning his first 19 professional fights, Clay became the youngest World Heavyweight Champion in history, defeating Sonny Liston by TKO on February 25, 1964, and declaring to the reporters at ringside “I am the greatest.” Shortly after the match, he announced he had converted to Islam and had changed his name, first to Cassius X (given to him by Malcolm X), and later to Muhammad Ali (by Elijah Muhammad).

“People had moved away from boxing. It was a huge deal in America in the 1940s and 1950s and then they wrote it off,” former President Bill Clinton told the BBC. “Then here comes Muhammad Ali, first as Cassius Clay, looking like a ballerina in the boxing ring — reminding people it was a sport.”

“He made it exciting and meaningful again. He was entertaining and when he was younger he was always mouthing. He made it part theatre, part dance and all power.”

His refusal to be drafted into the army to fight in Vietnam in 1967 led to his being stripped of his boxing license and championships, as well as being convicted of a felony.

“It could have destroyed him but it didn’t, because people realized he had been very forthright and he was prepared to pay the price for his convictions,” said Clinton. “On balance he won more admirers than detractors.”

Ali’s objections to the war were not specifically with the draft, but were due moreso to his religious beliefs and his feelings about racial injustice in the United States. He said that war was against the teachings of the Qur’an.

“Why should they ask me to put on a uniform and go 10,000 miles from home and drop bombs and bullets on brown people in Vietnam while so-called Negro people in Louisville are treated like dogs and denied simple human rights,” Ali said in 1966. “I ain’t got no quarrel with the Vietcong. No Vietcong ever called me ‘ni**er.’”

The U.S. Supreme Court eventually overturned his conviction in 1971. His three legendary fights with the late Joe Frazier highlight the second half of his career. The first fight at Madison Square Garden, dubbed the “Fight of the Century,” was a clash of cultures and styles that divided the country and blacks.

Ali’s constant taunts of the then-champion Frazier as being an “Uncle Tom,” “White Man’s Champion,” and a “Gorilla” added more heat to the fight, and for many years after the fact. Ironically, Frazier openly supported Ali’s right not to fight in Vietnam.

Frazier defeated Ali in a 15-round decision, his first professional loss. Ali won the non-title rematch at Madison Square Garden on January 28, 1974 in a 12-round decision setting up the epic match on October 1, 1975 known as the “Thrilla in Manilla.”

After 14 hellacious rounds, Ali won the fight when trainer Eddie Futch refused to let Frazier, who was blind in one eye, come out for the 15th. Ali would say after that fight that it was the closest he had come to death.

The last Frazier fight proved to be the peak of Ali’s in-ring career. After losing the title in February 1978 to Leon Spinks, Ali won his third and final championship just seven months later when he defeated Spinks in the rematch.

After briefly retiring in 1979, he came back in 1980 to challenge then-champion Larry Holmes and lost by TKO. Ali also lost his final fight in 1981 and retired for good.

Since his retirement, his once boisterous voice has been largely silenced by Parkinson’s disease — which he was diagnosed with in 1984, but had began to show signs as early as 1978. He often requires assistance from his wife Lonnie and rarely appears in public.

“As a young man, he had the most beautiful physique; His legs were prettier than most women’s,” Lonnie Ali said. “This disease has transformed him into something different. The man called the ‘Louisville Lip,’ because he spoke so loquaciously… it has silenced him somewhat.

“His movement is not as fluid and as beautiful as it was. He is still able to reach people with his eyes and his smile.”

Ali has traveled throughout the world on humanitarian missions to feed starving people. He has also worked with the Make-A-Wish-Foundation and the Special Olympics and is the namesake of the Muhammad Ali Boxing Reform Act, a federal law that regulates professional boxing to protect boxers from crooked promoters and poor health and fight conditions.

“I know a good humanitarian when I see one,” said Today Show host Ann Curry. “He’s changed the world, made children less hungry and people more equal. Those are the things that make you immortal.”

The Muhammad Ali Center opened in 2005, the same year he received the Presidential Medal of Freedom, and cost $60 million to construct. It was created as an education complex, a shrine to the legacy of his social activism.

“Muhammad and I always envisioned an organization that would use Muhammad’s life as a model to encourage people everywhere to ‘keep their eyes on the prize,’ to work hard to reach their potential and to achieve their dreams,” Lonnie Ali recently told the Washington Post.

At the party, Ali leaned against a rail and raised his right hand to wave to the crowd. He walked on his own but was often assisted by his wife and his sister-in-law. Lonnie also said that her husband, known for talking about how “pretty” he was, had mixed feelings about the landmark birthday.

“He’s glad he’s here to turn 70,” she said. “But he wants to be reassured he doesn’t look 70.”

Follow Jay Scott Smith on Twitter at @JayScottSmith