During the 1970s, Peter Berlin became a sex symbol of gay culture, a real-life Tom of Finland who photographed himself in parks, train stations and other cruising grounds.

Last Thursday, the man who created that character — Armin Hagen Freiherr von Hoyningen Huene — was in New York to celebrate his new book, “Peter Berlin: Icon, Artist, Photosexual.” Arbiters of contemporary downtown gay culture lined up to pay homage.

“So great to meet you,” said Marc Jacobs, who arrived from Paris and went directly to BookMarc, his West Village bookstore, for the book signing. “I love your book.”

Now 76 and living in San Francisco, Mr. Huene no longer has the dewy physique that made him a fetish pinup model, not to mention a pioneer of the erotic selfie. But he still has a pageboy haircut and mischievous smile.

“I documented myself as Peter Berlin, because I was always intrigued by that mirror image,” Mr. Huene said.

After the book signing, the party moved to Le Chalet, the St. Moritz-in-Manhattan lounge on the eighth floor of Saks Fifth Avenue. The louche crowd included Jason Wu, King Princess, Omar Sosa, Silvia Prada, Mel Ottenberg, Kembra Pfahler, Peter Schlesinger, Eric Bowman, Shayne Oliver, Drew Elliott and Michael Bullock, the book’s editor.

Last to arrive around midnight were Jeremy O. Harris, the playwright, trailed by Hamish Bowles, the Vogue editor.

“I want to lean into the lessons Peter Berlin taught us,” Mr. Harris said. “A lot of the power of being queer comes from presenting yourself to the world unabashedly.”

Mr. Huene leads a quiet life these days. He retired Peter Berlin some decades ago, though the character makes very limited returns.

“I take a little speed to pick me up and I dress up,” he said at the after-party, where he held court in a corner. “But I hide a lot that I don’t want to see because my body has changed. And then I carry this big mirror from the living room to my bedroom, where I have poppers and a crack pipe. And then I get my hit and it catapults me.”

“I become Peter Berlin for myself,” he said.

Royal Treatment

Prince Albert II of Monaco was the first to arrive at his own party Monday night. He dawdled on the red carpet at the Plaza Hotel and playfully popped a strongman pose, filling in time before the arrival of celebrities including Bernadette Peters, Leslie Odom Jr. and Victor Garber.

“That can’t be the prince because he’s never been on time for one of these things,” said John F. Lehman Jr., a onetime Secretary of the Navy and cousin to the prince’s mother, the former Grace Kelly.

“The Princess Grace Foundation was founded 37 years ago by my father to honor my mother’s legacy, because she always wanted to help young emerging artists in the performing arts,” the prince said.

The gala recognized more than 30 college-age artists in theater, dance and film, as well as Chinonye Chukwu, a previous honoree whose new film, “Clemency,” won the Sundance Film Festival grand jury prize this year.

Guests included Maguy Maccario Doyle, Monaco’s ambassador to the United States, and Isabelle Picco, its representative to the United Nations; Tiler Peck; Aldis Hodge; Jon M. Chu; Jazmin Grace Grimaldi; Lynn Wyatt; and Ron Chernow.

In the billionaires’ corner sat John Gore; Phyllis and Dennis Washington; Amy and Brian France; and Jenny and John Paulson. If Jon B. Turk, the society plastic surgeon, recognized any of his clients, he was too discreet to say.

“I’m only in New York for 28 hours,” Prince Albert said. Directly after the ceremony, he would take a private jet to Paris to accept an honorary doctorate from E.S.C.P. Europe, described by a member of his staff as “the second or third best business school in France.”

That flight may have been an excellent chance to catch up on Season 3 of “The Crown,” the Netflix drama about his cousins-by-marriage, the British royal family. Has he been watching?

“Not on a regular basis, but there are some wonderful performances in that series,” the prince said diplomatically. “You always pick up things. There’s always room for improvement.”