Hugh Hefner, the founder of Playboy Enterprises, died last night of natural causes at age 91. Hefner was best known as the editor-in-chief of Playboy Magazine and for breaking down barriers in the conversations America has around sex.

He launched Playboy in Chicago in 1953 with a nude Marilyn Monroe as the first centerfold, though the photos were actually from a 1949 calendar shoot for which Monroe was never paid. The issue sold out, and though he never met her, Hefner credits Monroe with helping launch the magazine and make it a success. Hefner bought the crypt next to Monroe in the Westwood Memorial Park cemetery in Los Angeles in 1992 and will be buried there.

Hefner's image as a pipe-smoking, silk robe wearing libertine living in a mansion full of perfectly proportioned and sexually available women was beloved by many and derided by others. His Playboy Mansion parties were legendary, though it was alleged in a lawsuit that they enabled Bill Cosby's predatory behavior.

Hefner's legacy has been debated for decades, with some arguing that Playboy's status as an iconic American brand opened the door for sexual liberation and a lessening of the Puritanical values that have kept people sexually repressed and in the closet, with others arguing he profited off women's sexuality in a way that didn't actually enable female liberation. Holly Madison, one of Hef's former girlfriends and star of the reality show about the mansion Girls Next Door, wrote a tell-all in 2015, revealing the darker side of life as a Playmate.

Still, Hefner has been celebrated for his promotion of sexual openness and frankness in American culture, and for providing opportunities in print for more open discussion of homosexuality and topics around race. He was also a vocal supporter of reproductive justice, with Playboy being the first major national consumer magazine to advocate for legal abortion, New York magazine reports.

Celebrities, including Kim Kardashian and Carmen Electra, who both posed for the magazine, shared their condolences online:

Hugh's former girlfriend Kendrick Wilkinson told E! News in a statement, "He made me the person I am today. I couldn't be more thankful for our friendship and our times together. I will miss him so much but he will be in my heart forever."

Hefner's son, Cooper Hefner, also released a statement:

"My father lived an exceptional and impactful life as a media and cultural pioneer and a leading voice behind some of the most significant social and cultural movements of our time in advocating free speech, civil rights and sexual freedom," he shared. "He defined a lifestyle and ethos that lie at the heart of the Playboy brand, one of the most recognizable and enduring in history. He will be greatly missed by many, including his wife Crystal, my sister Christie and my brothers David and Marston, and all of us at Playboy Enterprises."

[h/t Page Six]

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