His ambitions carried him far from fashion into the worlds of politics and culture. Though his clients were mostly rich and conservative, he was a staunch supporter of the Socialist Party, a contributor to liberal causes and a patron and arbiter of literature, theater and music.
Most of all, though, he seemed to relish the controversy that his wealth, power and prickly personality brought him. Well before the death of Mr. Saint-Laurent in 2008, Mr. BergÃ© had become a social star in his own right.
âPeople may hate me or love me, but they all want to brag that they once sat next to me at a dinner party,â he once said.
There seemed to be no neutral opinions about Mr. BergÃ©, a man of slight build, exquisitely tailored suits and oval, horn-rimmed glasses, which gave him an owlish look. Hailed as a master of the business deal, he was also denounced in some quarters as a scoundrel who fully deserved the fine he was ordered to pay for insider trading.
After President FranÃ§ois Mitterrand put him charge of Parisâs opera houses, including the newly built Bastille Opera, Mr. BergÃ© scandalized the music world by firing Daniel Barenboim as its music and artistic director, contending that his salary was too high and that his plans for the house were too elitist.
But as Mr. BergÃ© noted gleefully, he used that and other controversies to increase attendance at the opera house. âParisians at this stage want a Barnum more than a Toscanini,â he said.
Philippe Collin, a film director and critic who knew Mr. BergÃ© for 40 years, said, âI think of him as a great Hollywood producer from the golden era.â
At the Saint Laurent atelier in Paris, a seamstress spoke of Mr. BergÃ©âs unstinting financial help to terminally ill colleagues, but another woman employed there called him a âmisogynistâ who promoted only men to the higher rungs.
At the Bastille Opera, employees of both sexes spoke sotto voce about Mr. BergÃ©âs âreign of terror,â which led to the resignations of much of the senior staff he had inherited. And fashion writers complained that negative reviews of Saint Laurent collections could get them banned â at least temporarily â from future shows.
Pierre BergÃ© was born on Nov. 14, 1930, on the tiny Ãle dâOlÃ©ron, off the Atlantic coast of France. His father was a civil servant, his mother a schoolteacher. Mr. BergÃ© moved to Paris as a teenager intent on becoming a journalist. Arrested during a political demonstration, he spent the night in jail with Albert Camus and then joined him for coffee when they were released the following morning.
After that chance encounter, Mr. BergÃ©, at a starry-eyed 19, became the editor and publisher of a left-wing magazine whose contributors included Camus and Jean-Paul Sartre. The publication did not last long, but it helped Mr. BergÃ© establish lasting friendships with Jean Cocteau and Christian Dior. And he became a companion of the painter Bernard Buffet, who became a mentor.
The defining moment in his life, as Mr. BergÃ© often said, was meeting Mr. Saint Laurent in 1958. Intense and introverted, Mr. Saint Laurent was already, at 23, a highly regarded designer for the House of Dior. âI instantly recognized his genius,â said Mr. BergÃ©, who was 29 at the time. The two men became lovers.
With Mr. BergÃ© as his manager, publicist and partner, Mr. Saint Laurent exhibited his first collection in 1962. By the 1970s, Mr. Saint Laurent was heralded as the most influential designer of his generation, epitomizing the modern woman with swagger and extending fashionâs range of expression by bringing pea jackets, motorcycle jackets and Cossack coats to haute couture.
For his part, Mr. BergÃ© demonstrated a business creativity that the fashion world had seldom seen before. In the 1960s, he expanded Saint Laurentâs operations from haute couture into the far more profitable ready-to-wear market, with boutiques in Paris, New York and other cities across the globe. When the haute couture operations needed capital in 1971, Mr. BergÃ© sold the ready-to-wear division to the Squibb Corporation, only to buy it back two years later.
In 1986, he arranged the sale of 25 percent of the Saint Laurent empire to Carlo de Benedetti, the Italian entrepreneur, and used the money to buy Charles of the Ritz, which owned a number of designer perfumes, including several Saint Laurent fragrances.
Then, in 1989, under Mr. BergÃ©âs guidance, the Yves Saint Laurent group became the first French design house to be listed on the Paris Bourse. Investor reaction was sensational. Trading had to be halted during the first two days because there were 28 buy offers for each of the 400,000 shares initially put up for sale. By 1990, the group was ringing up $500 million in annual sales.
But after profits and share prices plunged during the next few years, Mr. BergÃ© cut an extremely advantageous deal for himself and Mr. Saint Laurent in 1993 by selling the Yves Saint Laurent group for $655 million to Elf Sanofi, the French pharmaceutical giant. The two men agreed to continue to manage YSLâs haute couture operations.
In addition to their glittering business relationship, Mr. BergÃ© and Mr. Saint Laurent shared a sumptuous lifestyle that made them fixtures in European high society. They filled their grand Paris apartment with antique furniture and covered its walls with Impressionist, Cubist and contemporary paintings. They flew guests by helicopter to their chateau in Normandy, in northern France.
In Marrakesh, Morocco, they opened one of their villaâs buildings as a museum specializing in Islamic art. And in New York, they decorated their apartment at the Pierre Hotel with 19th-century Americana.
It was only in the 1980s that Mr. BergÃ©, who had always portrayed himself as an Ã©minence grise, began to step out of Mr. Saint Laurentâs shadow. Mr. BergÃ© said that the victory of FranÃ§ois Mitterrand and his Socialists in 1981, after 23 years of conservative Gaullist governments, persuaded him to raise his profile. âI was always a man of the left, though never a Marxist,â he said. âAnd I decided politics was interesting again.â
But strains in his relationship with Mr. Saint Laurent were also leading Mr. BergÃ© to cut a more public figure. Always timid, Mr. Saint Laurent became increasingly reclusive. In interviews, he admitted to struggles with alcoholism, an addiction to cocaine and nervous breakdowns. âYves was born with a nervous breakdown,â Mr. BergÃ© said dismissively.
By the mid-1980s the two men were living apart, though their business relationship apparently remained as strong as ever. While Mr. Saint Laurent seemed able to summon up only enough energy to design his collections, Mr. BergÃ© displayed boundless dynamism. He united designers showing in France into one group, known as the Chambre Syndicale, to promote the fashion industry. He was the founding president of the French Fashion Institute and a founder of the Museum of Fashion Arts, both in Paris. Turning couture into an instrument of diplomacy, he staged Saint Laurent expositions in Moscow and Beijing.
With xenophobia and anti-Semitism rising in France, Mr. BergÃ© contributed generously to S.O.S. Racisme, a defender of minorities. When the AIDS epidemic began, he helped organize outpatient care and became president of Arcad SIDA, which financed AIDS research and education. And as a publisher, he used his magazine, Globe, to push his favorite causes, often contributing mordant and outspoken columns.
Mr. BergÃ© did not mind risking Saint Laurent sales by his political activism. He offended some Saint Laurent clients by soliciting funds for the re-election of Mr. Mitterrand in 1988. The Gaullist candidate, Jacques Chirac, denounced Mr. BergÃ© as the âforemost representative of the Caviar Left.â And Jacques Calvet, the head of Peugeot, the automaker, publicly urged a boycott of Saint Laurent products. But the call went unheeded by most prominent consumers, who seemed to know where to draw the line between their politics and their necessities.
Mr. BergÃ© became a friend and trusted confidant of President Mitterrand. He was often invited to the presidentâs country home, where they discussed politics and culture during long walks in the woods. It was Mr. Mitterrand who appointed Mr. BergÃ© president of the Paris Opera, which opened a futuristic venue at the Place de la Bastille in 1989, in time to celebrate the 200th anniversary of the French Revolution.
Even as critics questioned his credentials to run the opera, Mr. BergÃ© poured fuel on the controversy when he fired Mr. Barenboim as the musical director of the Bastille Opera and replaced him with Myung-Whun Chung, a Korean-American conductor who at the time was not well known.
After that, hardly a month went by at the opera without disputes with singers and stagehands or with senior employees who left in a huff over Mr. BergÃ©âs autocratic style.
As opera czar, Mr. BergÃ© coordinated the Bastille Opera; the Palais Garnier, the famous older opera house; and the Salle Favart, the traditional home of the OpÃ©ra Comique. He admitted that he had failed in several of his goals. Instead of the promised 250 opera performances a year, he was rarely able to stage more than 140. During his four years at the helm of the Bastille, he said he could think of only two or three productions that were worth the price of admission.
âThe rest, for one reason or another, I havenât liked at all,â he said.
The critics generally agreed with him: The reviews were mostly brutal.
Still, like a circus impresario, Mr. BergÃ© gleefully pointed to the large audiences at the Bastille Opera as vindication of his stewardship. âPeople are curious about this building, which is so talked about,â he said. âHalf of them never set foot in an opera house before. Yet suddenly, the opera has become the heart of French cultural and political life. Itâs laughable.â
Success at the box office was not enough to keep Mr. BergÃ© in the job. Soon after conservatives won a landslide victory in French parliamentary elections in 1993, a new Gaullist government got rid of Mr. BergÃ© and replaced him with an interim director and then with Hugues Gall, the director of the Geneva Opera.
Mr. BergÃ© also began to have legal problems linked to his business deals. In 1994, he was indicted on charges of selling nearly $20 million of shares in the Yves Saint Laurent group before the company announced a 94 percent plunge in net income in September 1992. Convicted of insider trading, he was fined $600,000, which, on appeal, was reduced to $200,000.
Mr. BergÃ©âs sale of the company to Elf Sanofi only added to the scandal. For their 43.7 percent holding, Mr. BergÃ© and Mr. Saint Laurent were paid $286 million, or $158 a share, well above the stockâs $118 market price right before the sale.
Since 1996 Mr. BergÃ© had been president of Sidaction, a fund-raising organization dedicated to AIDS research and treatment. He was also a founder of the French weekly Courrier International and the gay magazine TÃªtu, and the chairman of the supervisory board at the newspaper Le Monde.
In March 2017, Mr. BergÃ© married his longtime partner, Madison Cox, a landscape architect and director of the Fondation Jardin Majorelle in Marrakesh, part of the Fondation Pierre BergÃ©-Yves Saint Laurent in Paris. Mr. Cox survives him.
Most recently, Mr. BergÃ© was working on two museums dedicated to Yves Saint Laurent that will open next month: in Paris in the former premises of the haute couture house, and in Marrakesh in a new building next to the Jardin Majorelle.
Age did not temper Mr. BergÃ©âs tough-minded assessments of himself and of others. Asked about an often unflattering portrayal of his relationship with Mr. Saint Laurent in the 2014 biopic âYves Saint Laurent,â he replied: âBelieve me, I was not happy to be there, supporting Yves, during those times. I did that because I was obliged to do that, because I loved him.â
And like another regal figure, Louis XV, who allegedly asserted that a deluge would follow his demise, Mr. BergÃ© seemed convinced that the world of fashion he helped create would not outlive him.
âThe time of Chanel, Balenciaga, Dior and, of course, Yves â well, that time is over,â he proclaimed in a 2015 interview with The New York Times. âTo me, that whole industry now â all money and marketing â it is all something like a lie.â
An earlier version of this obituary misidentified the king of France who was said to have predicted that a deluge would follow his demise. It was Louis XV, not Louis XIV.