The image of the renegade hell-raiser stayed with O'Toole for decades, although he gave up drinking in 1975 following serious health problems and major surgery.
He did not, however, give up smoking unfiltered Gauloises cigarettes in an ebony holder. That and his penchant for green socks, voluminous overcoats and trailing scarves lent him a rakish air and suited his fondness for drama in the old-fashioned "bravura" manner.
A month before his 80th birthday in 2012, O'Toole announced his retirement from a career that he said had fulfilled him emotionally and financially, bringing "me together with fine people, good companions with whom I've shared the inevitable lot of all actors: flops and hits."
"However, it's my belief that one should decide for oneself when it is time to end one's stay," he said. "So I bid the profession a dry-eyed and profoundly grateful farewell."
In retirement, O'Toole said he would focus on the third volume of his memoirs.
Good parts were sometimes few and far between, but "I take whatever good part comes along," O'Toole told The Independent on Sunday newspaper in 1990.
"And if there isn't a good part, then I do anything, just to pay the rent. Money is always a pressure. And waiting for the right part — you could wait forever. So I turn up and do the best I can."
The 1980 "Macbeth" in which he starred was a critical disaster of heroic proportions. But it played to sellout audiences, largely because the savaging by the critics brought out the curiosity seekers.
"The thought of it makes my nose bleed," he said years later.
In 1989, however, O'Toole had a big stage success with "Jeffrey Bernard is Unwell," a comedy about his old drinking buddy, the legendary layabout and ladies' man who wrote The Spectator magazine's weekly "Low Life" column when he was sober enough to do so.
The honorary Oscar came 20 years after his seventh nomination for "My Favorite Year." By then it seemed a safe bet that O'Toole's prospects for another nomination were slim. He was still working regularly, but in smaller roles unlikely to earn awards attention.
O'Toole graciously accepted the honorary award, quipping, "Always a bridesmaid, never a bride, my foot," as he clutched his Oscar statuette.
He had nearly turned down the award, sending a letter asking that the Academy of Motion Picture Arts and Sciences hold off on the honorary Oscar until he turned 80.
Hoping another Oscar-worthy role would come his way, O'Toole wrote: "I am still in the game and might win the bugger outright."
The last chance came in, for "Venus," in which he played a lecherous old actor consigned to roles as feeble-minded royals or aged men on their death beds. By failing again to win, he broke the tie for futility which had been shared with his old drinking buddy, Richard Burton.
O'Toole divorced Welsh actress Sian Phillips in 1979 after 19 years of marriage. The couple had two daughters, Kate and Pat.
A brief relationship with American model Karen Somerville led to the birth of his son Lorcan in 1983, and a change of lifestyle for O'Toole.
After a long custody battle, a U.S. judge ruled Somerville should have her son during school vacations, and O'Toole would have custody during the school year.
"The pirate ship has berthed," he declared, happily taking on the responsibilities of fatherhood. He learned to coach schoolboy cricket and, when he was in a play, the curtain time was moved back to allow him part of the evenings at home with his son.
O'Toole's death was announced by agent Steve Kenis, who said the actor had been ill for some time.
His daughter Kate said the family had already been overwhelmed by the expressions of sympathy.
"In due course there will be a memorial filled with song and good cheer, as he would have wished," she said in the statement.
AP writer Raphael Satter contributed to this report.
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