Gabrielle Bonheur Chanel (August 19, 1883 – January 10, 1971) was a pioneering French couturier whose modernist philosophy, menswear-inspired fashions, and pursuit of expensive simplicity made her arguably the most important figure in the history of 20th-century fashion design.

Popularly known as Coco Chanel or "Mademoiselle" by her inner circle, she was born in the small city of Saumur, France in 1883, although she asserted she was born in 1893, in Auvergne. Her mother died when Chanel was six, and shortly afterward her father abandoned her and her four siblings; the Chanel children were then placed in the care of relatives and spent some time in an orphanage. After a couple affairs with generous wealthy men - a military officer and later an English Industrialist - she was able to open a shop in Paris in 1910 selling ladies' hats, and within a year moved the business to the fashionable Rue Cambon. Her influence on haute couture was such that she was the only person in the field to be named on the List of TIME Magazine's 100 most influential people of the 20th century.

In 1922 Chanel No. 5 perfume was introduced by Chanel. Pierre Wertheimer became her partner in the perfume business in 1924. Wertheimer owned 70% of the company; Coco Chanel received 10% and her friend Bader 20%. The Wertheimers continue to control the perfume company today.

The influential Chanel suit, launched in 1923, was an elegant suit comprising a knee-length skirt and trim, boxy jacket, traditionally made of woven wool with black trim and gold buttons and worn with large costume-pearl necklaces. She also popularized the little black dress, whose blank-slate versatility allowed it to be worn for day and evening, depending on how it was accessorized. Although unassuming black dresses existed before Chanel, the ones she designed were considered the haute couture standard. In 1923, she told Harper's Bazaar that "simplicity is the keynote of all true elegance."

The nickname Coco was evidently acquired at La Rotonde, a cafe frequented by members of a French cavalry regiment and numerous of the great artists who flocked to Paris' Montparnasse section at the turn of the 20th century. It was there that Chanel, then a cabaret singer, performed a song called "Qui qu'a vu Coco," and the name stuck. (Other sources state that her audiences cried "Coco" when they wanted an encore, while further sources state that the song was called "Ko Ko Ri Ko," French for "Cock-a-doodle-do.")

Chanel was set up in business by a lover, Étienne Balsan, a French textile heir, and her love affairs with the artist Paul Iribe, the Duke of Westminster, Grand Duke Dmitri of Russia, and British sportsman Boy Capel all had a considerable influence on the stylistic evolution of her often male-inspired fashions. She never married. She almost married the Lord Westminster but declined, noting "There are a lot of duchesses, but only one Coco Chanel."

For more than 30 years, Gabrielle Chanel made the Hôtel Ritz in Paris her home, even during the Nazi occupation of Paris, during which time she was criticized for taking a German military officer as a lover. She maintained an apartment above her Rue Cambon establishment and also owned Villa La Pausa in the town of Roquebrune on the French Riviera. However, she spent her latter years in Lausanne, Switzerland and is buried there in a tomb surrounded by five stone lions.

One of her common quotes is: "Fashion is not simply a matter of clothes. Fashion is in the air, born upon the wind. One intuits it. It is in the sky and on the road."

Chanel has been portrayed on the Broadway stage by Katharine Hepburn in a musical by Andre Previn and Alan Jay Lerner, and on screen by the French actress Marie-France Pisier.

The House of Chanel in Paris, under Karl Lagerfeld, remains one of the top design houses today.