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 points in his first defence against Larry Holmes in June the same year.
But it is a mark of the esteem in which the American 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 scraped a thin split-decision win over Norton 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, George Foreman, Joe Frazier, Leon Spinks and Jimmy Young.
Norton 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. 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.”
Former champion Mike Tyson, who visited Norton in hospital, tweeted: “Ken Norton was always nice to me even when I was just an amateur fighter. He always treated me like I was somebody. Remarkable man.”
And Lennox Lewis also tweeted: “RIP Ken Norton – Former World Heavyweight Boxing Champ. Prayers from my family to his. Bless!”
Norton’s death was confirmed by his friend and former manager Patrick Tenore, 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, Norton 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 by 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. He never had a bad word about boxing or any of his opponents. This is a man you have never heard say an ill word about anybody,’’ Tenore added.
Norton was inducted into the International Boxing Hall of Fame in 1992. The IBHOF said its flags would fly at half-mast yesterday as a mark of respect.
IBHOF executive director Ed Brophy said: “Ken Norton was one of the stand-outs of the talent-filled 1970s heavyweight division. 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.”
1943: Ken Norton is born on 9 August, in Jacksonville, Illinois.
1963: Starts boxing in the United States Marine Corps, claiming a 24-2 record on the way to three All-Marine heavyweight titles.
1967: Turns professional and wins his first bout against Grady Brazell by knockout.
1968: July 1970: Builds up a steady series of wins before he is beaten by Jose Luis Garcia on July 2, 1970.
1970: August: Beats Roy Wallace to start a 14-fight unbeaten streak.
1973: March - Defeats Muhammad Ali to win the North American Boxing Federation (NABF) heavyweight champion title.
September - Ali avenges the loss to Norton, beating him in a split decision in Inglewood, California.
1974: Fights George Foreman for the WBC and WBA heavyweight titles in Caracas, Venezuela, but the bout is stopped in the second round, with Norton losing by TKO.
1975: Regains his NABF title with a fifth round TKO defeat of Jerry Quarry before avenging the loss to Garcia by knocking him out in the fifth round.
1976: Fights Ali for the third time at Yankee Stadium in New York. The world title was on the line after Ali regained it with an eighth-round knockout of Foreman. Ali wins narrowly.
1977: Defeats Jimmy Young before being awarded the WBC heavyweight title.
1978: Loses his WBC title to Larry Holmes in Las Vegas in his first title defence on a split decision.
1981: Loses his last-ever professional bout to Gerry Cooney at Madison Square Garden then announces his retirement.
1986: Suffers a near-fatal car crash which leaves him with slurred speech.
1989: Inducted into the World Boxing Hall of Fame.
2011: Following years of charity work, Norton begins to suffer from ill health.
2012: July - Suffers a debilitating stroke.
2013: September 18 - Passes away in a care facility in Arizona from congestive heart failure.