He is poet and prophet, Buddhist bard “born in a suit,” a wandering Jew ever searching. A man of many generations, Leonard Cohen is still debonair, “looking like a Rat Pack rabbi.” His languorous voice grows deeper year by year as he gets us on his wavelength with recurring themes of love, religion, sex and loss.

Leonard Norman Cohen was born in Montreal in 1934, into an upper-middle-class Jewish family. His mother was the daughter of a Talmudic scholar, Rabbi Solomon Klonitzki-Kline, his paternal grandfather, Lyon Cohen, a leader of the Canadian Jewish community. Nathan Cohen, his father, worked in the clothing business and died when his son was 9 years old. Cohen has talked about having had a “messianic” childhood and the strong sense that he was going to do something special, that he would “grow into manhood leading other men.” He was also “well aware that he was a ­Kohen, one of a priestly caste.”

A poet in the 1950s who wrote “Let Us Compare Mythologies” (1956) and a novelist in the 1960s with “The Favorite Game” (1963) and “Beautiful Losers” (1966), Cohen became disappointed with his lack of financial success and moved to the United States to pursue a career as a singer-­songwriter. His first album, “Songs of Leonard Cohen,” was released in 1967 and now, 45 years later, Cohen has put out “Old Ideas,” his 12th studio album, while embarking on a tour that will spin him in circles around Europe and North America.

In 1969 he told The New York Times: “There is no difference between a poem and a song. Some were songs first and some were poems first and some were simultaneous. All of my writing has guitars behind it, even the novels.”

In taking on this artful dodger, Sylvie Simmons, a well-known British rock journalist and the author of biographies of Neil Young and Serge Gainsbourg, bumps up against the inherent difficulty of telling the story of a storyteller. “I’m Your Man” demonstrates that it’s hard to write about a writer whose work is so language- and phrase-specific, so intimate and distant at the same time, perpetually engaged in the dance of seduction.

One reads Simmons’s hefty volume longing for a bit more historical context or counterpoint; Cohen came of age against the backdrop of World War II, the growing sexual revolution, the advent of LSD, and so forth. But once one realizes it is unrealistic to expect the biographer to write with the same gift of voice and precision as the artist, there comes great joy. There is a familiarity to much of Simmons’s material, the sense of being on the inside, as though the reader were sitting at the table during the conversations Simmons reports, and the overall experience is of a thoughtful celebration of the artist’s life.

And, it turns out, she tells us an enormous amount that even I, a Cohen aficionado, didn’t know, including exactly how Jewish Cohen’s upbringing was — he was steeped in Judaism — and that his religious exploration included a brief period as a Scientologist. This detail illuminates the line in Cohen’s song “Famous Blue Rain Coat,” “Did you ever go clear?,” an explicit reference to Scientology that until now was always opaque to me.

It was in London in 1960 that Cohen heard about Hydra, a small Greek island, sunny, warm, a colony of writers, artists and thinkers from around the world. With his inheritance from his grandmother, Cohen bought a house there for $1,500 and began a long relationship with a now celebrated woman called Marianne (Ihlen), not to be confused with the slightly more celebrated muse Suzanne (Verdal), whom he didn’t actually bed — or the second Suzanne (Elrod), the mother of Cohen’s two children, Adam and Lorca.

In the mid-1960s in New York, Cohen met Judy Collins and played her a few songs. She immediately recorded “Dress Rehearsal Rag” and “Suzanne,” and released them on “In My Life” in 1966. A short but fruitful relationship with Joni Mitchell is echoed in Mitchell’s classic songs “Chelsea Morning” and “Rainy Night House,” the second of which makes reference to Mitchell spending the night in Cohen’s mother’s house. Listening to the song again with the knowledge of their relationship adds a newfound resonance. Simmons’s illuminations of Cohen’s artistic cross-pollination give the reader the experience of dipping into cultural ephemera — the kind of extended liner notes that all fans love.

Women play a huge role in Cohen’s life — his need for female affection, along with his difficulty in remaining involved, is the stuff of legend. The biography features some brilliant passages on marriage, Buddhism, therapy and Cohen’s book “Death of a Ladies Man” (1978). In later years, Cohen has frequently quoted a line from his poem “Titles,” which was part of a collection, “Book of Longing”: “My reputation as a ladies’ man was a joke / that caused me to laugh bitterly / through the ten thousand nights / I spent alone.” In the mid-1990s a Swedish interviewer asked Cohen about love. “I had wonderful love, but I did not give back wonderful love,” he said. “I was unable to reply to their love. Because I was obsessed with some fictional sense of separation, I couldn’t touch the thing that was offered me, and it was offered me everywhere.”

Other surprises: Cohen’s decision to add stops at mental hospitals to his 1970 European tour, akin to what Johnny Cash did with prisons; and his persistent experience of war. Cohen was in Cuba at the time of the Bay of Pigs invasion of 1961, and in 1973 he traveled to Jerusalem to sign up on the Israeli side in the Yom Kippur War. He was assigned to a U.S.O.-style entertainer tour in the Sinai Desert and performed for the troops up to eight times a day.

In 1993, Cohen retreated to the Mt. Baldy Zen Center near Los Angeles and in 1996, three years into his stay, he was ordained a Zen Buddhist monk, taking the Dharma name Jikan, meaning a kind of silence. Cohen spent five years at Mt. Baldy, most of it working as the assistant and chauffeur to the Zen master Joshu Sasaki Roshi.

By 2004 Cohen had come down from the mountain and was living in Montreal when, Simmons tells us, he discovered that while he was gone, Kelley Lynch, his business manager and friend, had stolen almost all of his money. Cohen ultimately got a judgment against Lynch, but most of the money could not be recovered. He was broke and forced back on the road, only to find that his fan base had continued to grow and that he’d gone from being a cult hero to an icon, especially in the United States, where there are now multiple generations of Leonard Cohen fans. With his children grown and with children of their own (Cohen became a grandfather for the second time in 2011, when his daughter, Lorca, had a child with the singer ­Rufus Wainwright), it seems that Cohen is ­finally able to allow the love in.

Simmons has deftly narrated Cohen’s evolution, bringing the past into the present and reminding us of the breadth of the journey. “I’m Your Man” is an exhaustive biography, an illumination of an artist who has repeatedly said he’s not much of a self-examiner. Among the book’s side effects is that it sends you back to the source material; as you’re reading, you find yourself craving Cohen’s music in the background. In her interview excerpts, Simmons captures the elliptical nature of ­Cohen’s speech, the wry turns of phrase that are almost like stand-up comedy. Behind it all are a smirk and a wink; you know that Cohen knows how absurd it all is.

And in the end, this biography has the oddest effect: as soon as you finish reading it you feel an overwhelming impulse to go back and begin again, revisiting the story with what you’ve learned along the way. As Leonard Cohen sings in “Anthem”: “Ring the bells that still can ring / Forget your perfect offering / There is a crack in everything / That’s how the light gets in.”