Anita Roddick, founder of the Body Shop cosmetics chain, died on Monday evening after suffering a major brain hemorrhage, her family said.
Roddick, 64, was with her husband and two daughters at a hospital in Chichester, southern England, when she died at 6:30pm.
She had been admitted to the hospital on Sunday evening, having collapsed after complaining of a sudden headache.
"Mrs Roddick was admitted to the hospital's intensive care unit, and her husband Gordon and two daughters, Sam and Justine, were with her when she died," a statement from the family said.
Roddick announced in February that she was suffering from the viral disease hepatitis C, contracted through a blood transfusion during the birth of her youngest daughter, Sam, in 1971. She also suffered from cirrhosis of the liver, a common long-term effect of the disease.
Roddick set up the first Body Shop -- selling its own brand of simple, environmentally friendly cosmetics, skincare and related products -- in the southern English town of Brighton in 1976.
It now has more than 2,000 stores in more than 50 countries and became part of the French giant L'Oreal Group in July last year. However, it has retained its brand identity and is run independently within L'Oreal from its base in Britain.
Roddick was made a Dame of the British Empire as part of the Queen's Birthday Honours in June 2003.
Tributes poured in for her soon after her death, with environmental group Greenpeace's executive director John Sauven describing her as an "incredible woman" who would be "sorely missed."
"She was an amazing inspiration to those around her, not just in environmental and human rights issues, which were two of her passions," Sauven said.
"When you look at it today, and how every company claims to be green, she was living this decades ago. She was a true pioneer," he said.
British Prime Minister Gordon Brown chimed in, saying he was "deeply saddened" to hear of Roddick's death, saying in a statement: "She will be remembered not only as a great campaigner but also as a great entrepreneur."
"As one of this country's most successful businesswomen she was an inspiration to women throughout the country striving to set up and grow their own companies," Brown said.
Human rights group Amnesty International, AIDS charity Body & Soul, and the anti-death penalty organization Reprieve also paid tribute to her life, providing a measure of the various causes Roddick was well-known for supporting.
L'Oreal CEO Jean-Paul Agon said Roddick would be sorely missed.
"Anita was quite simply an extraordinary woman: inspired, visionary, very brave and extremely generous," he said in a statement.
The Body Shop International's current chairman, Adrian Bellamy, said in a statement that Roddick "leaves us with an enduring legacy which will long guide the affairs of The Body Shop ... It is no exaggeration to say that she changed the world of business with her campaigns for social and environmental responsibility."