Like Chanel, the subject of her book, Edmonde Charles-Roux epitomizes French style. She is an aristocratically handsome woman of 61, wearing a navy jersey dress by Chanel, strands of pearls, pearl button earrings. A brown Gucci bag rests by the foot of her chair. She appears to be wearing no makeup but lipstick; her hair is pulled back neatly in a bun.

Charles-Roux has spent her life at centers of glamor and power: daughter of a French diplomat who grew up in Prague and Rome; twice-wounded nurse while serving in the French Resistance; journalist extraordinaire, involved in the early days of the magazine Elle and longtime editor-in-chief of French Vogue; award-winning novelist; wife of the French minister of the interior, the No. 3-ranking official in the new Socialist government.

But of all her accomplishments, she is best known as the friend and official biographer of Chanel, the woman who brought fashion into the 20th century by paring clothing to a pure, modern form that has enabled the Chanel empire to flourish to this day. Chanel -- who modified the elaborate hat of the day, designed dresses so simple they made the corset obsolete, led women to bobbed hair, introduced fake jewelry and the little black dress at a time when black was the color only of mourning, started women wearing jersey and simple knit suits, conceived the woman's bathing suit and invented a renowned fragrance, No. 5, her lucky number.

"She didn't create fashion, she created style," says Charles-Roux, who dined with Chanel, attended films with her, and, ultimately, learned the lies Chanel confected about herself, lived and took to her grave.

"She never told the truth -- never," says Charles-Roux. "She was living, hoping that the right man would ask her the right question -- will you marry me? But her background absolutely prevented the right man from asking the question. She was the daughter of a peddler and a poor woman, born in a hospital at a time when a decent girl even of modest origins would have a child at home. Everything in her past was upsetting to Gabrielle Chanel." Myth and Reality

Gabrielle Chanel, who died in 1971 at the age of 87, unmarried and alone, had woven such a legend about her life that, according to Charles-Roux, she had come to believe the Cinderella myth: that she had left her native province, Auvergne, in a simple cotton apron and wooden shoes, that her father had been a horse breeder, that she had been raised by lovely old aunts and had eloped with a handsome officer. "She got obsessed by that creation that was her legend and couldn't face the truth, even when there was no more hope of marriage," says Charles-Roux.

Charles-Roux discovered that Chanel had been born a peasant, illegitimate, and left in a convent orphanage. At 18, she worked as an assistant shopkeeper in Moulins. After a false start as a singer in a concert hall, where she got her nickname Coco, she moved to a chateau near Paris as the mistress of a gentleman horse breeder and discovered her own talent through the admiration others had for the clothes and hats she made for herself. With the financial help of yet another wealthy lover, she opened shops selling hats and some clothes in 1913 in Deauville and, when the war neared, in Biarritz. By the mid-1920s, when she was approaching 30, she was, as Charles-Roux has called her, "the empress of creation in France," head of a prestige house in Paris with international clients.

When Charles-Roux published her Chanel biography in 1975, many French were angry. She is still sensitive to criticism she received in Le Figaro. "I know how much a certain press prefers legends to the truth," she says. She has responded with still more insight into Chanel, a massive and remarkable photo-documentation, "Chanel and Her World," published first in France two years ago and available now in English and Japanese at a time when the Chanel style is particularly flourishing.

Both the Chanel fashion and perfume businesses continue to grow; the accessories are being exquisitely renewed. There is even a new Chanel film, "Chanel Solitaire." Thousands of women in Japan turned out to hear Charles-Roux discuss Chanel on a recent tour. Early this year, the Chanel boutique on the rue Cambon was bombed by liberationists -- they wanted to strike at the heart of French prestige.

"Fashion is not what one thinks it is," said Charles-Roux, during a brief stay at the French Embassy. "It is not frivolity, but one of the signs of change, of the time, of the way of living. And, with Chanel, of the possibilities of women."

Nor is she surprised that women today, Nancy Reagan among them, have adopted the Chanel style as a daily uniform. "Extravagant fashion in times of recession and economic difficulty all around the world is just not the thing to do, no matter how beautiful it is," she says. "Women now have an active life and the Chanel clothes were created for an active life. Chanel became what she was in 1919 when women were first free to walk alone in the streets, to have jobs . . . the first steps in an active life."

Today's woman, she says, can find comfort in a time of change with things that are familiar. "I want to look simple and I know how I look in a Chanel suit. I don't know exactly how I will look in something else," says Charles-Roux. And when there is much that is disturbing in the world "these clothes are not disturbing anybody. Are we not in a mood when nobody wants to be disturbed because there are so many disturbing things?"

Fashion, like politics, survives when it reflects the needs of the people. "When power loses the music of the streets it is the downfall. Especially in a country like France, where everything comes from the streets. Fashion comes from the street. The best songs come from the street -- not the Rolling Stones system, but Piaf, Mistinguett, Chevalier. If you don't listen to that you are done for.

"Chanel understood that things would never go backwards. Even after winning a war one would never go back to the pompous, frivolous life of before. The whole changes of Chanel have been inspired by the reality of life and of politics." Exile and Return

Charles-Roux was the sixth person Chanel asked to write her official biography. The others gave up in frustration. "Could I ask where you were born?" Charles-Roux asked Chanel. Chanel answered with the name of a town that never existed. "I realized she was working against the writer, hoping it would never be learned, for example, that she was born in Saumur. It would be like a stocking when you catch the first stitch."

In 1969 Charles-Roux discovered the address and went to see a first cousin of Chanel's who was a train-crossing guard. "I knocked on the door and his wife said that he will never see me. I said I would like to know how he spent his holidays with her, what games they played, nothing more." But he refused.

The next day Chanel received a letter from the cousin. "She had never seen this man for 50 years, and still he was of that strong French peasant family that believes whatever happens we stick together," says Charles-Roux. The letter told Chanel of the Charles-Roux visit and enclosed the letter he had received requesting the interview.

"Chanel exploded in public. She called me awful French words. I thought, it is her right. From 1969 to her death in 1971 , we were brouille'e estranged . But I was free. I could go on with my research without betraying her."

The new book chronicles the developing style of Chanel and how it sprang from the life of the time. It includes her birth certificate and the program from her debut in a concert hall in 1905 and the music and words to the song "Qui Qu'A Vu Coco," from which she got the name Coco. One photograph, taken by Richard Avedon, then 16, shows Chanel posed, unbeknownst to her, under a poster reading "Pourquoi Hitler." Chanel spent 13 years in self-exile following a liaison with a German officer during World War II. But then, provoked by Dior's success, she returned to Paris and reopened her shop in 1954 at the age of 71. Shortly after, says Charles-Roux, "the street became entirely dressed in Chanel copies."

The book also includes a photo of a nude young woman collaborator being led through the streets by jeering Frenchmen after the liberation in 1944 -- treatment Chanel barely escaped, says Charles-Roux, who suggests that Chanel was spared through the intervention of her former lover, the duke of Westminster, with the help of his friend Winston Churchill. A Duke, Don Juan and Vogue

Charles-Roux's career as a journalist and author began at France Soir and Elle, and took off after Christian Dior encouraged her to go to French Vogue. She wrote about theater at first. But soon after she started the editor, Michel de Brunhoff, to whom she has dedicated her latest Chanel book, felt he couldn't go on after his 16-year-old son had been shot by the Nazis. "He sat me next to him for two years, listening, choosing photos, going into the fabrication of the magazine and one day he said, 'Well, I am going. Try and do the job.' "

She did it for 16 years, but says she had a falling-out with the ownership over the declining space devoted to culture. And she was told the magazine was not frivolous enough. "Why should the rich woman be frivolous? They said the readers are rich so they don't read. No, I don't think so. I think they read because they are rich. She has more time to read a book. Why should a woman who is well off be considered like a doll, just occupied in dressing? I think it is wrong. For France it is certainly wrong."

She left the magazine at age 45 -- "It was embarrassing." But in her spare time she had written a book, a biography of Don Juan of Austria, and two months later she had a contract. Her novel "Forget Palermo," translated into 17 languages, won the prestigious Prix Goncourt. Her latest success, "A Sicilian Childhood," was inspired by the memoirs of the duke of Verdura, Sicilian grandee and 20th-century jewelry designer.

But the stories of Chanel continue to fascinate Charles-Roux, and the audiences she attracts. As she noted in a recent speech at the Maison Francaise at Columbia University, "When women's hats were covered with jewels and bows and even birds in nests, yes, really, she made light hats. And when asked why, Chanel answered, 'How could women think with such a thing on their heads?' " Hats were important, Charles-Roux reminded the audience, because they were a sign that one was not a member of the working class.

Chanel cut her hair short, Charles-Roux remembers her saying, "because it is a crashing bore to stay more than an hour to coif one's hair." When Chanel showed up at a Diaghelev ballet with her hair short, other women followed.

"Chanel thought false jewelry could be truer than true jewelry and felt ashamed when she saw women in the street with rich diamonds. It obliged her to think about people who cannot pay, and so she would invent something quite as beautiful that anyone could buy," says Charles-Roux.

Chanel decided that it was normal for several people to have the same dress. She reasoned, "Why shouldn't the dress be like the body of a car? I think women have many other ways of changing a dress by invention and imagination and making their own creation by adding things. Wearing it in an intelligent way will make the dress different." The American press dubbed her simple black dress "the little Ford."

"We should take the lesson of Chanel," Charles-Roux said, "and wonder if change is not something we study to find out why people are so afraid of change, and why people like even better what is not all right but exists rather than what you can do to make it better." Two Suits

Now Charles-Roux is occupied with the new Socialist government. She works at the ministry of the interior five days and the other two days in Marseille, where her husband, Gaston Defferre, is still mayor.

She answers letters, "25 to 30 letters a day of sheer misery. 'My husband is in prison and I can't pay the rent and the children are left alone' . . . 'My boy of 15 has been opening a car, I don't think he is a real burglar' . . . "

Danielle Mitterrand, wife of the president, spends 9 a.m. to 6 p.m. each day "answering every single letter of that sort," Charles-Roux says. Charles-Roux has told Madame Mitterrand that the couturiers would like to make clothes for her as they have for the wives of other presidents, but her choice -- a sign of the times, perhaps -- is to shop quickly at Louis Feraud and Torrente, two shops near the Elysee Palace.

Charles-Roux would like to redecorate the ministry but, she says, the word is out that no redecorating should be done. Unlike at the White House, the rule is, "If it is clean you keep it the way it is," she says a bit unhappily. "The ministry is delicious but it is certainly not decorated."

Charles-Roux insists that fashion is not endangered under the new government. She points out that Pierre Cardin will open a couture house in Peking. And Yves Saint Laurent, whom she sees as the modern-day "real creator, the boy wonder," has told her, "It is not on French clientele that I can keep my house open."

At first she seemed unsure about this comment by the couturier Pierre Balmain: "French fashion resisted the German occupation, we can resist the Socialists." But now she is comfortable with it. "French style is a question of tradition, of knowledge that has been going on for centuries. Whatever happens, fashion will be created in France . . . What kept fashion going during the real hell of the German occupation when the idea of going into a couture shop to buy a dress didn't cross my mind a minute? It was the pleasure of creating. C'est une necessite' de creation, the need to create. Balmain is completely right."

Such a time as this, of cutting back, is in keeping with French style, she says. "Young girls I know are not upset about wearing the same thing a long time." She quotes Chanel: "One of my suits is at its best after four years of wearing it -- like a good wine." And adds, "I think she is right."

Chanel, Charles-Roux adds, owned only two suits, one for working and one for Sundays. "And when she looked at the working suit and the elbows were popping out, she explained that that was the way a working suit should be. Only when it gets too shabby should you change. She was a real peasant girl."