Birkin, 76, had been suffering from health problems in recent years that had forced her to cancel concerts.
The cause of death and other details were not immediately known.
Birkin catapulted to fame through her turbulent relationship with legendary singer-songwriter Serge Gainsbourg and her heavily accented French, which became one of her signatures in her adopted home.
With her flared jeans, mini dresses, and distinctive fringe, Birkin was the ultimate It girl in the 1970s.
In 1984, Hermes named one of its handbags after her, which remains a sought-after status symbol.
Tributes poured in from across the country following her death.
President Emmanuel Macron led off by calling Birkin “a complete artist” who “sang the most beautiful words in our language”.
“Unimaginable to live in a world without your light in it,” singer Etienne Daho, one of her close friends, wrote on Instagram.
French Prime Minister Elisabeth Borne hailed her as an “unforgettable icon, a unique voice, and charm” who “with her music and her talent transcended generations”.
– Turbulent love affair –
Born in London, Birkin crossed the Channel in 1968 at the age of 22 to star in a film alongside Gainsbourg, who was 18 years her senior.
It was the start of a 13-year relationship that made them France’s most famous couple, in the spotlight as much for their bohemian and hedonistic lifestyle as for their work.
Birkin, with her soft voice and androgynous silhouette, quickly became a sex symbol, recording a steamy duo with a growling Gainsbourg in 1969, “Je t’aime… moi non plus”.
Banned on radio in several countries and condemned by the Vatican, the song was a worldwide success.
“He and I became the most famous of couples in that strange way because of ‘Je t’aime’ and because we stuck together for 13 years and he went on being my friend until the day he died. Who could ask for more?” Birkin told CNN in 2006.
“So Paris became my home. I’ve been adopted here. They like my accent,” she said.
– Style icon –
The daughter of an actress and a naval officer, Birkin married James Bond composer John Barry, with whom she had a daughter, Kate. The marriage lasted three years.
She moved to France after meeting Gainsbourg on the set of a romantic comedy in which he was her co-star.
They had a daughter, Charlotte, who became a hugely successful actress and singer.
The musical and romantic relationship between Gainsbourg and Birkin was famously tempestuous.
During one of their raging rows, Birkin tossed herself into the River Seine after throwing a custard pie in Gainsbourg’s face.
She blazed her own trail after walking out on France’s favourite bad boy in 1980.
In her around 70 films she has worked with leading directors including Bertrand Tavernier, Jean-Luc Godard, Alain Resnais, James Ivory and Agnes Varda.
But she remained forever associated with Gainsbourg, who continued to write songs for her after their split, including “Les dessous chics” about lingerie being used to try to cover up a relationship on the rocks.
“It’s the most beautiful song about separation you could ever have,” Birkin told AFP in a 2018 interview.
Her life was marked by tragedy and obstacles.
Her oldest daughter, Kate Barry, a photographer, died in an apparent suicide in 2013.
She fought leukaemia in the late 1990s and in 2021 suffered a minor stroke.
Birkin is survived by her daughter with Gainsbourg, Charlotte, and another daughter Lou Doillon, a singer, from a 13-year relationship with French director Jacques Doillon.
AFP