Along with other postwar, second-generation immigrants like Bernard Malamud and Philip Roth, Puzo began his writing career with complex aspirations — to tell an autobiographical tale that explored the difficulties and allure of cultural assimilation in America. Born in Manhattan’s Hell’s Kitchen, the child of Neopolitan Italians, Puzo drew on his hardscrabble upbringing — his father deserted him and his six siblings when he was 12 — for his second novel, “The Fortunate Pilgrim.” His fictionalized version of his mother, Lucia Santa, is a stern and canny matriarch who negotiates her bicultural world with peasant wisdom and a streetwise eye. In the preface to a recent edition of the novel, Puzo claimed that his mother was the inspiration for Don Corleone. “Whenever the Godfather opened his mouth, in my own mind I heard the voice of my mother,” he said.

Even though the critics appreciated these early books, Puzo found himself broke and blocked as a writer at the age of 45. Figuring he could raise some cash writing a book that collected the many stories he’d heard about organized crime, he dashed off “The Godfather.” “I wished like hell I’d written it better,” he would later say. “I wrote below my gifts in that book.” But the desire to make a quick buck on Mafia sensationalism turned out to be a true devil’s bargain. Read all over the world, the book is regarded as his single achievement, and his regret — how many times must he have rewritten in his mind what he had believed were disposable sentences — must have been keen.

No doubt the millions of dollars he earned soothed his conscience somewhat, but Puzo’s sense of having betrayed his abilities continued to be played out in his writing career. He became a compulsive gambler, blowing much of what he made in Vegas. This set up a cycle that required him to write another commercial blockbuster — more crime, more garish sex — just to keep pace with his losses at the craps tables. The post-”Godfather” novels — “Fools Die,” “The Sicilian,” “The Fourth K” and “The Last Don” — rehash, with wildly varying degrees of skill, the bloody operatics that made him famous. In “The Sicilian” he does it with a deliciously exacting eye for the island’s landscape and history; in “The Last Don,” he’s on automatic pilot, spooling out television-style clichis.

Still, by relying on the gangster story, surely the most worn-out plot in 20th century American books and movies, Puzo did manage to write the master narrative for the genre. The “Godfather” saga — the novel and the first two films (sorry, I just refuse to concede the existence of “Godfather III”) — is the benchmark telling of the American myth of ruthless acquisition. Don Corleone is a fantasy figure for have-nots (not for nothing did Snoop Dogg title one of his albums “The Doggfather”) as well as haves. The Don’s deep sense of serrated grievance makes him an American everyman: “[Don Corleone] had long ago learned that society imposes insults that must be borne, comforted by the knowledge that in this world there comes a time when the most humble of men, if he keeps his eyes open, can take his revenge upon the most powerful.”

In Corleone’s dictatorial yet strangely soothing exercise of absolute power, we find the benevolent monarch who will make the trains run on time, protect us and, best of all, set straight our enemies. Guys in corner offices and guys on corners both trill with delight at the Mafia boss’s ever cagey regard for the world around him. His steely paranoia — “Keep your friends close, but keep your enemies closer” — makes him the quintessential American realist hero. But Corleone is also a gushy sentimentalist, a papa who weeps for his boys (when he’s not giving them a good smack). In this way, the Don serves as the ultimate patriarch, the strong, loving father you wished you had. Perhaps this explains his story’s global appeal. That, and the cool way people get blown away.

In “The Godfather,” Puzo also rather handily accomplished his goal of depicting the immigrant’s struggle in the New World. Italian-Americans may have chafed at his having capitalized on the unpleasant reality of the Mafia in a way that doubtlessly perpetuated ugly stereotypes — “That’s Mafia style, isn’t it? All olive oil and sweet talk,” says one character — but in a strange way they also embraced the tale. (For years “The Godfather” theme song was a staple at many Italian-American weddings.) The book and film had, at least, made their community visible. And, certainly, the role of the Corleone family as outsiders in a white-bread, straight world sounded a larger theme for many immigrants. In between the guns and the cannoli, Puzo had, in fact, made his story of ethnic isolation and striving accessible to millions of readers.

Even when writing with the meter running, Puzo could unreel the kind of phrasing that slips permanently into the language. If you know only the film adaptations of “The Godfather,” you might be surprised to discover that the novel is nearly word-for-word the same story (except for a weird digression about Sonny’s girlfriend’s gynecological problems). The novel’s talky dialogue was pared down to epigrammatic utterance by Puzo for the movie — “Luca Brasi sleeps with the fishes” — thus the movie feels more Shakespearean and less like the gritty realist genre effort it was meant to be. The novel’s wise guys don’t appear on the scene like archetypal forces of nature as do their cinematic counterparts. Instead, they act like refugees from a Hemingway novel — ambivalent about the codes by which they’ve chosen to live. (Indeed, Puzo’s first novel, “The Dark Arena,” was set in post-World War II Europe and can be characterized as a sharply done, more sexually knowing update of “The Sun Also Rises.”) Aside from codifying an American myth and gracing it with memorable phraseology — “I made him an offer he couldn’t refuse” — Puzo’s most notable achievement in “The Godfather” may be bringing up the volume on crime’s social dimension, the chitchat of murderous men, and making possible logomaniacal progeny such as “Pulp Fiction.”

Puzo’s last unpublished novel was titled “Omerta” (the Cosa Nostra code of silence). As poet laureate of the Mafia, he was unable to escape telling its highly marketable tales; judging by the endless stream of top-grossing Mafia books and movies, you’d guess that Mafia entertainment far out-grosses the actual criminal enterprise. The siren call of this big money may have led him astray from high-minded art, but it assured him a place of honor in the carnival tent of pop culture. In his famous novel he wrote, “Italians have a little joke, that the world is so hard a man must have two fathers to look after him, and that’s why they have godfathers.” Indeed, Puzo’s iconic creation, Don Corleone, had two fathers — the pulp writer and the serious novelist. Together they made us all a storytelling offer we couldn’t refuse.