Norton reigned as world champion for three months in between being awarded the title by the World Boxing Council in March 1978 and losing it on a split decision in his first defence against Larry Holmes in June the same year.
Despite his fleeting time as champion, it is a mark of the esteem in which Norton was held that so many boxing greats felt the need to mark his passing from congestive heart failure in a care facility in Arizona on Wednesday.
Holmes, who took Norton's WBC title after 15 brutal rounds, said: "He had such a physique and was strong. Even many years later, he still looked the same. He was well built and he was a very humble guy."
Norton, who had been in poor health and suffered a stroke last year, fought in arguably the strongest era of heavyweight boxing history along with the likes of Muhammad Ali - he was only the second man to defeat him - George Foreman, Joe Frazier, Leon Spinks and Jimmy Young.
He ended his career with a record of 42 wins, seven losses and one draw, and was most famous for breaking Ali's jaw in the first of their three fights, which he went on to win on points in San Diego in 1973. Ali would take the decisions in their rematches, though many questioned the judges' verdict on the decider at Yankee Stadium.
Foreman, who stopped Norton in two rounds in Caracas in 1974, tweeted: "They called us all handsome. Muhammad they called pretty. But the fairest of them all was Ken Norton." Lennox Lewis also tweeted: "RIP Ken Norton - Former World Heavyweight Boxing Champ. Prayers from my family to his. Bless!"
"Ken Norton was always nice to me," said former world champion Mike Tyson, who visited him in hospital. "Even when I was just an amateur fighter. He always treated me like I was somebody. Remarkable man."
Norton's death was confirmed by Patrick Tenore, his friend and former manager, who said: "He was a fighter. He fought a tough battle and we thought he was out of the woods. He was a warm and generous man. He was a champion and a fighter and bright-eyed and anxious to see the next day and a dear friend of 20 years. Everyone will miss him. He never said a bad word about anyone."
Norton fought twice more after his loss to Holmes, retiring after a first-round defeat to Gerry Cooney at Madison Square Garden in 1981.
Following his boxing career, he made several film and television appearances before he suffered a near-fatal crash in 1986 when his car veered off the on-ramp to the Santa Monica Freeway in Los Angeles.
Despite being struck with ill health in later life, Tenore says Norton never blamed this on his professional boxing career, which began with a win over Grady Brazell in 1967. "Ken Norton never blamed anyone for anything," said Tenore. "He never had a bad word about boxing or any of his opponents."
Norton was inducted into the International Boxing Hall of Fame in 1992. The organistation said its flags would fly at half-mast on Thursday as a mark of respect.
"Ken Norton was one of the stand-outs of the talent-filled 1970s heavyweight division,"said IBHOF executive director Ed Brophy. "He was a great fighter in the ring and a great person outside of it. The Hall of Fame joins the worldwide boxing community in mourning his passing."