Boxing legend Muhammad Ali dies at 74

Muhammad Ali, the silver-tongued boxer and civil rights champion who famously proclaimed himself "The Greatest" and then spent a lifetime living up to the billing, is dead.

Ali died Friday at a Phoenix-area hospital, where he had spent the past few days being treated for respiratory complications, a family spokesman confirmed.

He was 74.

"After a 32-year battle with Parkinson's disease, Muhammad Ali has passed away at the age of 74. The three-time World Heavyweight Champion boxer died this evening," Bob Gunnell, a family spokesman, told NBC News.

Ali had suffered for three decades from Parkinson's Disease, a progressive neurological condition that slowly robbed him of both his legendary verbal grace and his physical dexterity. A funeral service is planned in his hometown of Louisville, Kentucky.

Even as his health declined, Ali did not shy from politics or controversy, releasing a statement in December criticizing Republican presidential candidate Donald Trump's proposal to ban Muslims from entering the United States. "We as Muslims have to stand up to those who use Islam to advance their own personal agenda," he said.

The remark bookended the life of a man who burst into the national consciousness in the early 1960s, when as a young heavyweight champion he converted to Islam and refused to serve in the Vietnam War, and became an emblem of strength, eloquence, conscience and courage. Ali was an anti-establishment showman who transcended borders and barriers, race and religion. His fights against other men became spectacles, but he embodied much greater battles.

Born Cassius Clay on Jan. 17, 1942 in Louisville, Kentucky, to middle-class parents, Ali started boxing when he was 12, winning Golden Gloves titles before heading to the 1960 Olympics in Rome, where he won a gold medal as a light heavyweight.

He turned professional shortly afterward, supported at first by Louisville business owners who guaranteed him an unprecedented 50-50 split in earnings. His knack for talking up his own talents — often in verse — earned him the dismissive nickname "the Louisville Lip," but he backed up his talk with action, relocating to Miami to train with the legendary trainer Angelo Dundee and build a case for getting a shot at the heavyweight title.

The new champion soon renounced Cassius Clay as his "slave name" and said he would be known from then on as Muhammad Ali — bestowed by Nation of Islam founder Elijah Muhammad. He was 22 years old.

Divorced three times and the father of nine children — one of whom, Laila, become a boxer — Ali married his last wife, Yolanda "Lonnie" Williams, in 1986; they lived for a long time in Berrien Springs, Michigan, then moved to Arizona.

In recent years, Ali's health began to suffer dramatically. There was a death scare in 2013, and last year he was rushed to the hospital after being found unresponsive. He recovered and returned to his new home in Arizona.

In his final years, Ali was barely able to speak. Asked to share his personal philosophy with NPR in 2009, Ali let his wife read his essay:

"I never thought of the possibility of failing, only of the fame and glory I was going to get when I won," Ali wrote. "I could see it. I could almost feel it. When I proclaimed that I was the greatest of all time, I believed in myself, and I still do."

Credit: NBC News