Profile: Leonard Cohen

His brand of introspective folk-inspired warbling may have gone out of fashion for the best part of two decades, but with the western world once again suffering a crisis of confidence, who better than the 74-year-old 'godfather of gloom', 'poet laureate of pessimism' and 'high priest of pathos' to take centre stage?

A man with a well-hidden but wry sense of humour, the delicious irony in the fact that Cohen's rehabilitation is down to Simon Cowell will not have been lost on the bedsit bard. The X Factor's purveyor of vacuous pappy pop single-handedly sparked an unexpected Indian summer and a 1m windfall for Cohen when he decided that the first record released by Alexandra Burke, the winner of this year's successor to Opportunity Knocks, would be a cover version of Cohen's 1984 classic 'Hallelujah'. It seems sure to be the Christmas No.1.

Not that Cohen had ever really gone away. In particular, 'Hallelujah', the emotional song that Cohen distilled from 80 verses to six stanzas "on the carpet in my underwear, banging my head on the floor", has become a recognised means of alerting audiences that it's time to reach for the hankies. When Marissa died in popular American TV drama The OC, it was to the strains of 'Hallelujah'. The song came to a wider audience through Jeff Buckley's haunting cover in 1994, a track which went to the top of the US iTunes chart last March. And the Rufus Wainwright version was featured in the film Shrek. It has also been covered by Damien Rice, Jon Bon Jovi, kd lang, John Cale and classical singer Katherine Jenkins. There's even a Welsh-language version.

Cohen's signature tune is a paean to a doomed love affair with a woman who cares little for music and is more concerned with a game of sexual humiliation. Rufus Wainwright declared Cohen "the greatest living poet on earth" and 'Hallelujah' is a poignant, earthy take on the two issues that dominate his life: faith and sex. His conclusion that sex is the great driver of humanity is no surprise given that Cohen was a notorious womaniser.

"I had a great appetite for the company of women," he once said. "And for the sexual expression of friendship." Cohen says he was too much of a coward to ever get married, but he had relationships with actress Rebecca De Mornay, Velvet Underground singer Nico and Janis Joplin, plus countless others. He even had two children with Suzanne Elrod, yet he was never fulfilled by his affairs, a fact borne out by two of his most famous songs. 'So Long Marianne' was about a failed relationship with another man's wife, while 'Suzanne' was about his unrequited longing for an old friend's ex-wife.

If Cowell helped bring Cohen back to international prominence, the singer's unerring eye for a bad relationship played its part too. Cohen's recent sell-out 30-date tour in which Chancellor Alistair Darling and hundreds of thousands of fans paid 75 a ticket (with black market tickets changing hands at 250 each) would never have happened had he not met Kelley Lynch, the manager and lover who swindled him out of $10m, leaving him with just $150,000 to show for 30 years of recording and album sales in the millions. She even sold the rights to his back catalogue. He successfully sued her for $9m, but by then the bombed-out blonde who spent Cohen's money on gigolos and shopping splurges on Rodeo Drive was a wreck of a woman with debts and depression.

With little prospect of recouping any money from Lynch, he had no choice. "I had to go to work," said Cohen of his first tour for 15 years. "I had no money left."

Lynch had worked her way through Cohen's money because the singer, notoriously bad with his own finances, had given his manager complete power of attorney over his affairs in the early 1990s when he was in a bad way. Depressed and marginalised, he was drinking three to four bottles of wine every evening and had become intensely melancholy. He never enjoyed performing but by 1994 he was so angst-ridden that he withdrew from a tour, no longer able to face his fans, and entered the Mount Baldy Zen Buddhist Monastery in the San Gabriel Hills just outside Los Angeles.

Very conscious of his Jewishness, Cohen said he "didn't need another religion" – but he did need peace and order. Dressed in Buddhist robes, shaven-headed and renamed Jikhan (Silence) by the monastery's charismatic founder Kyozan Joshu Sasaki Roshi, he stayed at Mount Baldy for five years, although he says he wasn't a good monk. "Much of the time, Roshi and I were two buddies drinking. He likes sake, I tried to convert him to French wine, but he was very resistant. But we both agree about Cognac and Scotch."

When a spiritually refreshed Cohen emerged to find that he was broke, it was the first time in his life that he'd known penury. Growing up in Montreal, his father Nathan, a Polish Jew, had built up a substantial clothing store and although he died when Cohen was just nine, he left him a trust fund that made him a man of independent means. He used that freedom to set up folk combo the Buckskin Boys before going to McGill University where his first book of poems, a tribute to his father called Let Us Compare Mythologies, was one of five collections that established him as one of Canada's foremost poets. His music never sold well in America, where his dark social polemic on the subjects of war, suicide, relationships and depression played less well than in Canada and Europe. But when Cohen wanted to take his music seriously he moved to New York, setting up shop at the Chelsea Hotel alongside poet Allen Ginsberg, Beat writer Jack Kerouac and Warhol. He was soon spotted by John H Hammond, the Columbia Records executive who signed Bob Dylan, Bruce Springsteen, Billy Holiday and Aretha Franklin, and his debut album earned him cult status and friends such as Dylan, Joan Baez and Jimi Hendrix.

Yet by the mid-1970s the time for his tortured soul-baring seemed to have passed. Cohen only returned to prominence after Jennifer Warnes' hugely popular tribute album Famous Blue Raincoat in 1987 was followed by his comeback album I'm Your Man in 1988, a synthesiser epic which marked a dramatic change in direction. But it's the mournful songs of his heyday that will be the ones sought out by a new generation of fans alerted by his X Factor fame. "I don't consider myself a pessimist," he once said. "I think of a pessimist as someone who is waiting for it to rain. And I feel soaked to the skin." Gloom never goes out of fashion.

One of Cohen's early concerts, at Aix-en-Provence in France, was invaded by rowdy Maoists. One of them took a potshot at the singer, the bullet smashing a light behind him. "They're tough critics, the Maoists," he said.

Cohen joined the Israeli forces during the Yom Kippur War of 1973, where he toured the front and at one stage sheltered from a firefight in a foxhole where he shared a bottle of cognac with an unlikely fan, Ariel Sharon.

His first concert was a disaster. Supporting Judy Collins, above, at a 1967 anti-Vietnam War concert, he took to the stage and froze with stage-fright.

Cohen once wondered if his CDs should come with razor blades.

Cohen has become happier in old age: "A kind of mist, a kind of distress over everything, has lifted. I feel tremendously relieved that I'm not worried about my happiness."

Gordon Brown revealed last week he would be downloading X Factor winner Alexandra Burke's version of Cohen's 'Hallelujah'.