“Even his egocentricity added to his charm,” one of his editors said. Photograph by Richard Meek / The LIFE Images Collection / Getty

“Herzog” is the book that made Saul Bellow famous. He was forty-nine years old when it came out, in 1964. He had enjoyed critical esteem since the publication of his first novel, “Dangling Man,” in 1944, and he had won a National Book Award for “The Adventures of Augie March” in 1954. But “Herzog” turned him into a public figure, a writer of books known even to people who don’t read books—an “author.” At a ceremony honoring the success of “Herzog” at city hall in Chicago, Bellow’s home town, a reporter asked the mayor, Richard J. Daley, whether he’d read the novel. “I’ve looked into it,” Daley said.

You get enough people saying that and you have a best-seller. “Herzog” sold a hundred and forty-two thousand hardcover copies and remained on best-seller lists for forty-two weeks. Paperback rights to that novel and Bellow’s earlier books were bought for big advances, and, for the first time in his life, Bellow had money. A house he owned in upstate New York that he had complained about for years as a white elephant he gave away, to Bard College, to get the tax deduction.

“Herzog” also marks the moment when, in terms that Bellow’s son Greg later used to describe his father, “young Saul” began to turn into “old Saul.” Authors are objects of cathexis, some of it idolizing, some of it envious, a fair amount both. Their names are on every short list; their views are solicited on every topic. Bellow ended up with the most impressive trophy haul in his generation of American writers: three National Book Awards, a Pulitzer Prize, and a Nobel. He also got drawn into political, generational, and culture-war-type disputes of the sort that, as a young man, he had been careful to avoid. Bellow was sharp, well read, and observant, and he prided himself on his street smarts. But he was a fictionalist, not an editorialist—a bird, as he liked to say, not an ornithologist.

Recognition magnifies idiosyncrasies. Personality traits affectionately condoned “in the family” display differently on the big stage. A characteristic of Bellow’s mentioned by nearly everyone who knew him was his touchiness. He cut people who commented critically on drafts he sent them for comment, and he imagined conspiracies operating behind negative reviews or press coverage that he regarded as less than flattering. He broke with old friends after political disagreements over dinner. These reflexes did not serve him well out in the arena. After he got in trouble with multiculturalists for asking an interviewer “Who is the Tolstoy of the Zulus, the Proust of the Papuans?,” he published a Times Op-Ed piece in which, while attempting to distance himself from the remark, he called his critics Stalinists. This did not clear the air.

There’s something else that people who knew Bellow almost always mention, which is that he was uncommonly good-looking. Also charming, seductive, and totally game: he fell for beautiful women and beautiful women fell for him. Sexual attention matters to everybody; it mattered exceedingly to Bellow. He was described by women who knew him intimately as domineering but needy. Successful seduction seems to have been a form of validation, and a prescription refillable as necessary.

In short, Bellow was a man who liked to be stroked, and who was suspicious of strokers. Factor in brains and an exceptional gift and you get a fairly complicated piece of work. And every book that has been written about Bellow by someone who was close to him is to some degree hostile toward its subject. This is true of books by Bellow’s literary agent Harriet Wasserman (“Handsome Is”: title says it all), his son Greg (“Saul Bellow’s Heart”), and his first biographer, James Atlas. Two biographers-in-waiting, Mark Harris and Ruth Miller, eventually admitted defeat and published books in which Bellow figures as an enchanting but exhausting tease.

Zachary Leader met Bellow only once. That was in 1972, at a party near Harvard, where Leader was a graduate student and Bellow was being awarded an honorary degree. Leader says that Bellow seemed bored, and he remembers nothing of what Bellow said. In the genre of Bellow biography, this counts as a credential.

Leader’s “The Life of Saul Bellow: To Fame and Fortune” (Knopf) is the story of young Saul. It opens in Russia, where Bellow’s parents and his three siblings were born, and it closes with “Herzog.” (A second volume is promised.) As a piece of research and writing, the book is worthy in multiple ways. The best thing about it is that Leader understands literature—he is a professor of English who teaches in London—so he’s interested in Bellow for the right reasons, and his critical assessments are informed and disinterested. He knows his way around the inbred worlds of the little magazines where Bellow made his name and the college literature departments where, for many years, he earned his living.

Not the best thing about the book is the length. Together with the unusually informative notes, the text is more than seven hundred and eighty pages, and there are forty years still to go. That’s over a hundred pages longer than Atlas’s biography—which is also well researched and well written, and which Leader cites and acknowledges frequently. The trouble is not that Leader is verbose. The trouble arises from the central problem of Bellow criticism, which is how to pull the life apart from the art. Leader is alive to the problem; he devotes much of his introduction to it. But he hasn’t entirely solved it.

“I am an American, Chicago born” begins the famous first sentence of “The Adventures of Augie March.” The author of that sentence was actually an illegal immigrant, Canada born, and the words were written in Paris. Bellow’s father, Abraham Belo, was born in a shtetl inside the Pale of Settlement. He began his career in St. Petersburg as a produce broker, specializing in Egyptian onions and Spanish fruit. The family seems to have been quite well off. Abraham had used a forged document to work in St. Petersburg, and, when this was discovered, he was arrested and convicted. He may have gone to prison. But he managed to escape and, in 1913, to get his family to Canada.

They settled in Lachine, outside Montreal, where Abraham tried farming, and where, in 1915, Saul was born. When the farm failed, the family moved into the city and Abraham took up bootlegging, a venture that ended even more disastrously. In 1924, he moved again, to Chicago, and engaged some bootlegging associates to smuggle his wife and children across the border to join him.

Abraham spent the rest of his life in Chicago, and he ended up running a retail coal business. But he never really learned English—Yiddish was the language at home—and he never became a citizen. He had no passport and no driver’s license (which didn’t prevent him from driving). Saul did not become an American citizen until 1943.

But Chicago was a city of immigrants. It also had a large Jewish population—by 1931, according to Leader, nearly three hundred thousand in a city of 3.3 million. All the Bellow children assimilated happily and all became well off. Saul is often associated with the University of Chicago, where he taught for many years as a member of the legendary Committee on Social Thought. He was a student there, but for less than two years. He had to withdraw for financial reasons (a truck driver was killed in an accident at his father’s coal yard and the insurance had lapsed), and he transferred to Northwestern, from which he graduated in 1937.