French tycoon Liliane Bettencourt, the world's richest woman, sat atop the L'Oreal empire and ran a philanthropic foundation, but faced an old age clouded by dementia and legal drama.

Bettencourt, who died late on Wednesday at the age of 94, was the main shareholder in the world's top cosmetics company L'Oreal, with a personal fortune estimated by Forbes magazine in March at $39.5 billion (33 billion euros).

"We all had a deep admiration for Liliane Bettencourt, who... was committed to (L'Oreal's) success and its development," L'Oreal CEO Jean-Paul Agon said in a statement.

Bettencourt was rarely seen in public after leaving the L'Oreal board in 2012, but her name remained in the headlines as members of her entourage were charged with exploiting her failing mental health.

Bettencourt had been declared unfit to run her own affairs in 2011 after a medical report showing she had suffered from "mixed dementia" and "moderately severe" Alzheimer's disease since 2006.

The complex legal case involved a bitter feud with her only daughter, Francoise Bettencourt-Meyers, as well as unscrupulous friends, and even dragged in former president Nicolas Sarkozy.

In 2008 Bettencourt-Meyers, who is on the L'Oreal board, filed a lawsuit against her mother over funds the magnate had given to a celebrity photographer and confidant.

Liliane Bettencourt insisted at the time that she was in perfect health.

Eight members of Bettencourt's entourage were convicted in May 2015 of fleecing her, including photographer Francois-Marie Banier, who was given a four-year suspended prison sentence on appeal.

Patrice de Maistre, who managed Bettencourt's vast fortune, was sentenced to 30 months in prison, 12 of which were suspended, and a fine of 250,000 euros.

- Envelopes of cash -

De Maistre was accused of getting Bettencourt to hand over envelopes of cash to members of Sarkozy's rightwing party during his 2007 presidential campaign.

The charges against Sarkozy were dropped in October 2013 due to lack of evidence.

Bettencourt was born Liliane Schueller on October 21, 1922, in Paris, where her father Eugene Schueller was marketing an early hair dye formula he had invented in 1907.

Schueller, the son of bakers from the eastern Alsace region, initially named his company Aureale, but changed it to L'Oreal in 1939.

Liliane, who had lost her mother when she was five years old, adored her father, whom she liked to say "taught me the meaning of hard work."

The product of a strict Catholic upbringing, she started helping out with the company at age 15, sticking labels on bottles of shampoo and mixing cosmetics.

- Controversy over Nazi links -

She was, however, no stranger to controversy.

Both her father and her husband Andre Bettencourt were accused of being ardent Nazi collaborators during World War II.

Her husband, who died in 2007, had been a member of a French fascist group during the war but sought forgiveness from the Jewish community in its aftermath.

In addition to playing a key role in L'Oreal, Andre Bettencourt later served as a government minister under president Charles de Gaulle.

Inheriting the L'Oreal fortune from her father in 1957, Liliane Bettencourt chose not to be directly involved in running it.

Bettencourt long enjoyed the company of artists, and her Bettencourt-Schueller foundation funded a range of films and art projects over the years, in addition to medical research and literacy projects.

L'Oreal is one of the world's biggest cosmetics group with nearly 90,000 employees in 140 countries and sales of 25.84 billion euros in 2016.

In addition to the L'Oreal Paris and Maybelline New York mass-market brands, the group also markets luxury cosmetics under brands such as Lancome, Ralph Lauren and Giorgio Armani.

L'Oreal also owns The Body Shop.