Annie Flanders, the ardent, russet-haired founding editor of Details magazine, the proudly independent chronicle of Downtown Manhattan in the 1980s, died on March 10 at an assisted living facility in Los Angeles. She was 82.

The cause was complications of Alzheimer’s disease, said the writer Martha Frankel, a friend and former Details contributor.

In the post-disco era of the early 1980s, a combustible mix of art, music and fashion erupted out of the nightclubs, boutiques and art galleries found mostly below 14th Street. That was Ms. Flanders’s territory, chaotic but symbiotic, and its tribes were her people. And though that world was tiny, its cultural impact — the artwork of Keith Haring and Jean-Michel Basquiat, the fashion designs of Isabel Toledo, Betsey Johnson and Stephen Sprouse, and even the shenanigans of a sassy club kid named Madonna — loomed large, and lingered.

“It was this mad collision,” Simon Doonan, the longtime creative director of Barneys New York, said in a phone interview. “There was a feeling that anything was possible. There were a couple of grown-ups in the room. Annie was one of them. She was able to make sense of the chaos and shape it into a magazine.”

Ms. Flanders didn’t invent downtown; it was a real place with real people, said Ruben Toledo, the Cuban born artist and husband of Ms. Toledo, whose exquisite, artfully feminine clothes were first shown in Ms. Flanders’s magazine. “But Annie was able to stand back and see the glamour in it and sell tickets to it,” he said.

“In a way,” he added, “she formed that ’80s culture, which became not just an American phenomenon but an international one. We who were in the trenches were just too muddy and dirty to see it ourselves.”

Ms. Flanders’s background was in fashion. She had worked in retail and spent a few years in Ethiopia jump-starting a clothing manufacturing effort there before, in the 1970s, overseeing the style pages of The SoHo News, the upstart competitor to the other local counterculture bible, The Village Voice, until folding in 1982.

With her shock of red hair and New York accent, Ms. Flanders was more Auntie Mame than Diana Vreeland — she was celebratory, not hortatory. She had a great nose, said Mr. Doonan, “for charismatic misfits and creative people.”

Ms. Flanders gathered many of them to start Details in the spring of 1982, funding the effort with $6,000 of her savings. The magazine’s co-founders included Stephen Saban, the acerbic British writer, nightclub enthusiast and SoHo News alum; Ronnie Cooke Newhouse — then Ronnie Cooke, before she married into the Newhouse publishing family — who was fresh out of art school; and Lesley Vinson, the young graphic designer who had laid out Ms. Flanders’s pages at The SoHo News.

The debut cover of Details looked like a slab of marble with the title carved into it, and at first the magazine’s covers were embellished with just one elegant portrait shot in black and white (which fit the budget but also the aesthetic). “Ephemera written in stone” was the graphic concept, said Ms. Vinson, the magazine’s art director.

Initial circulation was 10,000 — many copies were given away to people whose names were culled from the guest lists of nightclubs, which offered them in exchange for free or discounted ads. In the beginning, Details had no newsstand sales. The staff held mailing parties to stuff envelopes. Billy Idol dropped by one late night to lend a hand.

Details had a motto: “A party in a magazine.” “We go out so you don’t have to,” Mr. Saban liked to say.

Staff members rolled in to work in the late afternoon, a schedule suited to their nighttime behaviors; Ms. Flanders started her day at 4 p.m. (To streamline her evening routine, she often threw on a scarlet wig, which she named Mildred and which lived in her office.)

“We are not an intellectual magazine,” she told Judy Klemensrud of The New York Times in 1985, the year Details won an award from the Council of Fashion Designers of America. “We are strictly for people who have an artistic bent, or are fun-loving people. We represent a way of life: people who really like to laugh, have a good time, go out and care, at least some of the time, about what they wear.”

Mr. Saban covered nightlife, tartly. (Patrick McMullen took the photos that accompanied Mr. Saban’s column.) Cookie Mueller, the doomed avant-garde model, actor and mordant writer, was the art critic. “All of it is worthless,” she once wrote of the scene she inhabited, “but all of it is true, and that is something.”

Bill Cunningham, the iconoclastic fashion photographer, was another SoHo News contributor who followed Ms. Flanders to Details. His fashion coverage was scholarly and comprehensive. During his long career — his photos could be found in The Times for more than four decades — it was Ms. Flanders who gave him the most freedom, and he adored her, along with her quirky staff. (“Why are you wearing that plastic bag, Muffin?” he once inquired of Ms. Vinson, whose style was lighthearted punk.)

The photographer Marcus Leatherdale made veiled portraits of demimonde luminaries for a column called Hidden Identities: the performance artist Leigh Bowery in a beaded mask, a corset and a merkin (it was a challenge, Mr. Leatherdale said, to flag down a taxi for him afterward); Keith Haring dressed as a raffish Santa Claus; and Andy Warhol posing with a bust of Caligula, his face buried in his hands, though his spiky platinum wig and Rolex watch were clearly visible.

“I didn’t realize I was archiving an era that was going to be extinct,” Mr. Leatherdale said. “Of course, you think you will be 20 forever.” At first, Ms. Flanders paid him $35 a photo.

Some contributors, like Hal Rubenstein, the food and fashion journalist, worked cheerfully free of charge for a few years (he had a day job as a caterer), though Ms. Flanders covered his expenses for his restaurant column, “I’ll Eat Manhattan.”

When he reviewed Florent, the late-night canteen in the meat packing district, its owner, Florent Morellet, was furious at the publicity; the review drew crowds that overwhelmed the place. “It was bedlam,” Mr. Rubenstein said in a phone interview. “That’s how influential the magazine was.”

The entertainment journalist Michael Musto, who would go on to cover nightlife for The Village Voice, wrote movie reviews that were sometimes notable for their brevity: “Mentl” was his one-word summation the 1987 Barbra Streisand film, “Nuts,” a witticism that ended up as a Trivial Pursuit clue.

For a time, Lewis Grossberger, a humorist, wrote a column called Mental Notes, which once offered dating tips from Attila the Hun.

“We were all hatching,” said Ms. Cooke Newhouse, who married Jonathan Newhouse, now chairman of Condé Nast, in 1995 and who now runs her own London-based fashion advertising agency. “I was the fashion editor, but I didn’t know what that meant. Someone called to ask me to look at their cruise line, and I said, ‘We don’t take cruises.’”

Ms. Cooke Newhouse’s first article, for the first issue of the magazine, was about Susanne Bartsch, the glittering Swiss nightlife impresario who at the time had a clothing boutique on Thompson Street selling young avant-garde designers like John Galliano. Ms. Flanders put Ms. Bartsch on the cover.

“I wasn’t famous,” said Ms. Bartsch. “Nobody knew who I was. But Annie liked what I was doing, and she liked the newness of it.”

As for the magazine’s title, it came to Ms. Flanders one day when she was chatting with her daughter, Rosie, about school, as she recalled in the Times article: “‘Rosie, you’ve got to get the details, I love details. I want to know the whole story.’”

She was born Marcia Weinraub on June 10, 1939, in the Bronx to Dorothy (Lautman) and Ralph Weinraub, a real estate agent known as Lefty. She attended New York University for three years, studying retailing and journalism (and winning Miss New York University in 1959).

She worked as a buyer and fashion director for Gimbels department store, among other emporia, and then opened a funky clothing boutique, Abracadabra, on the Upper East Side in the late 1960s, the decoration of which involved a mirrored erector-set contraption salvaged from an old amusement park. She met her longtime partner, Chris Flanders, an actor turned contractor formerly named Christian Van der Put, when he helped her build a display for the store. He didn’t think the name Marcia fit her; to him, she was more of an Annie. So she adopted that name, along with his last name, though they never married.

In 1988, Details was bought by Advance Publications, the publishing empire of the Newhouse family, which owns Vogue, among other glossy titles, for a reported $2 million. Jonathan Newhouse was its publisher that first year, before moving to Paris in 1989 to oversee the company’s international titles.

Despite its popularity and influence, Details struggled financially, though at the time of its sale it had a paid circulation of 100,000. Ms. Flanders was fired two years later, and the magazine was reimagined as a men’s publication, with James Truman, a former Vogue editor, as its editor in chief. The magazine was closed in 2015.

In the 1990s, Ms. Flanders and her family moved to Hollywood, where she reinvented herself as a real estate agent, though she did not drive, working with her daughter, Rosie, who did. Her daughter survives her. Mr. Flanders died in 2007.

Decades never end neatly, and the ’80s were no exception. B 1989 the ranks of the downtown world that Ms. Flanders had so lovingly chronicled had been decimated by AIDS. Ms. Mueller died that year, as did thousands more.

“We thought it would last forever,” said Mr. Musto. “We thought the magazine would last forever.”