Hugh Hefner, who created Playboy magazine and spun it into a media and entertainment-industry giant — all the while, as its very public avatar, squiring attractive young women (and sometimes marrying them) well into his 80s — died on Wednesday at his home, the Playboy Mansion near Beverly Hills, Calif. He was 91.His death was announced by Playboy Enterprises, the New York Times reported. “You couldn’t talk politically,” Mr. Feiffer said in the 1992 documentary “Hugh Hefner: Once Upon a Time.” “You couldn’t use obscenities. What Playboy represented was the beginning of a break from all that.”Playboy was born more in fun than in anger. Mr. Hefner’s first publisher’s message, written at his kitchen table in Chicago, announced, “We don’t expect to solve any world problems or prove any great moral truths.”Still, Mr. Hefner wielded fierce resentment against his era’s sexual strictures, which he said had choked off his own youth. A virgin until he was 22, he married his longtime girlfriend. Her confession to an earlier affair, Mr. Hefner told an interviewer almost 50 years later, was “the single most devastating experience of my life.”In “The Playboy Philosophy,” a mix of libertarian and libertine arguments that Mr. Hefner wrote in 25 installments starting in 1962, his message was simple: Society was to blame. His causes — abortion rights, decriminalization of marijuana and, most important, the repeal of 19th-century sex laws — were daring at the time. Ten years later, they would be unexceptional.“Hefner won,” Mr. Gitlin said in a 2015 interview. “The prevailing values in the country now, for all the conservative backlash, are essentially libertarian, and that basically was what the Playboy Philosophy was.“It’s laissez-faire. It’s anti-censorship. It’s consumerist: Let the buyer rule. It’s hedonistic. In the longer run, Hugh Hefner’s significance is as a salesman of the libertarian ideal.”The Playboy Philosophy advocated freedom of speech in all its aspects, for which Mr. Hefner won civil liberties awards. He supported progressive social causes and lost some sponsors by inviting black guests to his televised parties at a time when much of the nation still had Jim Crow laws. He was compared to Jay Gatsby, Citizen Kane and Walt Disney, but Mr. Hefner was his own production. He repeatedly likened his life to a romantic movie; it starred an ageless sophisticate in silk pajamas and smoking jacket, hosting a never-ending party for famous and fascinating people. The first issue of Playboy was published in 1953, when Mr. Hefner was 27 years old, a new father married to, by his account, the first woman he had slept with.He had only recently moved out of his parents’ house and left his job at Children’s Activities magazine. But in an editorial in Playboy’s inaugural issue, the young publisher purveyed another life: Hefner the man and Playboy the brand were inseparable. Both advertised themselves as emblems of the sexual revolution, an escape from American priggishness and wider social intolerance. Both were derided over the years — as vulgar, as adolescent, as exploitative, and finally as anachronistic. But Mr. Hefner was a stunning success from his emergence in the early 1950s. His timing was perfect. The brand faded over the years, and by 2015 the magazine’s circulation had dropped to about 800,000 — although among men’s magazines it was outsold by only one, Maxim, which was founded in 1995.Mr. Hefner remained editor in chief even after agreeing to the magazine’s startling decision in 2015 to stop publishing nude photographs. Mr. Hefner handed over creative control of Playboy last year to his son Cooper Hefner. Playboy Enterprises’ chief executive, Scott Flanders, acknowledged that the internet had overrun the magazine’s province: “You’re now one click away from every sex act imaginable for free. And so it’s just passé at this juncture.” The magazine’s website, Playboy.com, had already been revamped as a “safe for work” site. Playboy was no longer illicit. (Early this year, the magazine brought back nudes.)Mr. Hefner began excoriating American puritanism at a time when doctors refused contraceptives to single women and the Hollywood production code dictated separate beds for married couples. As the cartoonist Jules Feiffer, an early Playboy contributor, saw the 1950s, “People wore tight little gray flannel suits and went to their tight little jobs.” “We enjoy mixing up cocktails and an hors d’oeuvre or two, putting a little mood music on the phonograph and inviting in a female acquaintance for a quiet discussion on Picasso, Nietzsche, jazz, sex.”This scene projected an era’s “premium boys’ style,” Todd Gitlin, a sociologist at Columbia University and the author of “The Sixties,” said in an interview. “It’s part of an ensemble with the James Bond movies, John F. Kennedy, swinging, the guy who is young, vigorous, indifferent to the bonds of social responsibility.”Hefner was reviled, first by guardians of the 1950s social order — J. Edgar Hoover among them — and later by feminists. But Playboy’s circulation reached one million by 1960 and peaked at about seven million in the 1970s. Long after other publishers made the nude “Playmate” centerfold look more sugary than daring, Playboy remained the most successful men’s magazine in the world. Mr. Hefner’s company branched into movie, cable and digital production, sold its own line of clothing and jewelry, and opened clubs, resorts and casinos.