An explosive ninth round in which Fury was given a 10 count after reeling from a series of left hands before then being saved by the bell swung the contest in the new WBC, WBA, IBF and WBO champion's favour.
Usyk won 115-112 and 114-113 on two scorecards while the third judge saw it 114-113 for Fury, who felt he should have been given the decision.
Usyk has missed children's birthdays and even the birth of his daughter during his eight-month camp for the Fury fight, originally scheduled for February before the Briton suffered a cut in training.
His promoter Alex Krassyuk believed that Usyk was denied a knock-out victory when the referee stepped in as Fury looked about to hit the deck in round nine.
"I believe the referee saved Tyson from a knock-out and stole the ninth-round knock-out, which should have happened," Krassyuk said.
But Usyk said: "No knock-out, no problem."
"I don't think about it because we had a win."
Liverpool legend Steven Gerrard joined celebs Anthony Joshua and Cristiano Ronaldo to watch the Fury v Usyk fight in Riyadh.
Usyk was taken to hospital for a scan on an injury that his promoter Alex Krassyuk refused to disclose after inflicting the first loss of Fury's career in an enthralling clash that surpassed expectations.
An explosive ninth round in which Fury was given a 10 count after reeling from a series of left hands before then being saved by the bell swung the contest in the new WBC, WBA, IBF and WBO champion's favour.
Tyson Fury appeared to claim that he lost his showdown with Oleksandr Usyk because the judges sided with the Ukrainian over the war in Ukraine.
"I believe I won that fight," Fury said. "I believe he won a few of the rounds, but I won the majority of them, and I believe it was one of those what-can-you-do, one of them ... decisions in boxing. We both put on a good fight, best we can do.
"You know, his country is at war, so people are siding with a country at war."
An emotional Oleksandr Usyk shed tears for his late father after beating Fury to be crowned the undisputed heavyweight world champion on Sunday.
He shrugged off concerns that he might have suffered a broken jaw while reflecting on defeating Tyson Fury in a riveting battle in Riyadh.
Usyk said he wanted to focus on his family, rather than boxing, and he shed tears at the press conference as he remembered his late father who died just days after he won the Olympic heavyweight title at London 2012.
Tyson Fury is a dad-of-seven, has £300m in bank and has earned the right to surrender – so why didn’t he against Usyk, writes Sun boxing reporter Wally Downes Jr.
Read Wally's big fight verdict in the link, below.
Oleksandr Usyk addressed the media in the early hours of this morning after his stunning victory over Tyson Fury.
Usyk said: "We have a winner. There wasn't the knockout but no problem.
"We have a winner."
Tyson Fury says he is undecided about a rematch with Oleksandr Usyk after losing his unbeaten record in one of the biggest fights in boxing history.
"I'll have a holiday, go home, put it to the wife and kids I'll see what I want to do," the self-styled 'Gypsy King' told reporters after the fight.
How the big fight went down last night as Oleksandr Usyk became the undisputed heavyweight champion of the world with his stunning win over Tyson Fury:
Here is what we know about when the HUGE rematch will take place.
Saudi boxing chief, H.E. Turki Alalshikh, confirmed before the fight started that Fury vs Usyk II has been pencilled in for the weekend of October 12/13.
Alalshikh plans to have the rematch to kick off another Riyadh Season.
How SunSport's Chisanga Malata saw that dramatic ninth round when Tyson Fury was DROPPED:
Oleksandr Usyk is slowly but surely allowing the gap to be closed, which leads to him eating a big left hand flush in the corner.
Fury gets hurt and is stumbling around the ring. It was a left hand that did the damage.
Fury doesn't know where he is and is eating a barrage of crisp follow-up shots. He beats the count and the bell thankfully saves him.
Score: USYK 10-8
Matchroom Boxing chief and Anthony Joshua promoter Eddie Hearn has given his thoughts on Tyson Fury's stunning survival of the ninth round against Oleksandr Usyk.
He told DAZN: "How he survived the ninth [round]?
"I thought he was very lucky that the referee didn't jump in.
He showed unbelievable heart to stay on his feet and unbelievable composure coming out for the tenth and eleventh rounds.
"He was losing those rounds, but he was recovering."
Oleksandr Usyk faces only being able to call himself undisputed champion for a matter of weeks.
Usyk prevailed in what was been dubbed "the fight of the century" after beating Fury via split-decision in Saudi Arabia.
Fury lost his WBC title, while Usyk added to his WBA, IBF and WBO belts.
And despite all the attention and build up to the first undisputed heavyweight bout in over 25 years, his status will only last a fraction of that time.
Boxing journalist Dan Rafael has reported that the winner of tonight's bout will maintain the undisputed title for "less than two weeks".
It's said that both Fury and Usyk's contracts dictate that they must vacate the IBF title ahead of overdue mandatory challenger Filip Hrgovic's bout with Daniel Dubois.
Lennox Lewis - the last man to hold all the heavyweight titles - took to Twitter to congratulate Oleksandr Usyk for following in his footsteps and becoming the undisputed ruler of the division.
He tweeted: "Welcome to the club! z@Usykaa.
"Tonight we witnessed a crackin’ fight and history made.
"I was happy to welcome either one of these incredible champions to the Undisputed HW club and tonight it was Oleksandr The Great.
"Looking forward to seeing them do it again. @usykaa has proved that it never too late to add to your legacy. Congrats!
"Fury will learn from this and he’ll be back! Losing is also part of the game, it’s how u respond to a loss that makes all the difference."
Tyson Fury was quizzed about his suggestion that the judges gave Oleksandr Usyk the victory because his native Ukraine is at war.
He said: "It was what it was. It's not up to the fighters.
"One of the judges had me winning, two of them didn't. It was what it was."
Oleksandr Usyk has suffered a broken jaw and has been transported to the hospital.
So he will not be taking part in a post-fight press conference this morning.
Oleksandr Usyk had to be helped back to his dressing room by a member of his team.
The Ukrainian was spotted limping as he made his way backstage.
It's unclear what injury he suffered.
Oleksandr Usyk was quick to embrace his wife, Yekaterina, after fulfilling his dream of becoming undisputed heavyweight champion.
What a moment for the couple.
The ringside judges' scorecards for Usyk's coronation as undisputed heavyweight champion are in.
Oleksandr Usyk is the first undisputed ruler of the heavyweight division in 25 YEARS.
The last man to hold all the marbles was the great Lennox Lewis.
Usyk is now a TWO-DIVISION undisputed champion have previously conquered the cruiserweight weight class.
David Haye has claimed the referee saved Tyson Fury from being stopped in the ninth round.
The former WBA heavyweight champ said: "[He was] holding Usyk's arm back so he can't get the job done."
Tyson Fury's promoter said: "I think he won by a couple of rounds but that's what it is, we're not moaning.
"But there will be an immediate rematch.
"Tyson has said he wants a rematch and I see where he's coming from."
Tyson Fury has revealed he plans to exercise his rematch clause in his contract for the Riyadh rumble.
He said: "I'll be back, I've got a rematch clause."
He added: "For sure, we go back. Have a little rest up, spend some time with my family and we go again in October."
Usyk was quick to accept the challenge, saying of a second showdown with AJ: "Yes of course, I am ready for the rematch."
