LONDON (AP) — Gerald Cavendish Grosvenor, Duke of Westminster, spent his adult life dutifully stewarding vast wealth that he'd rather not have had.
The duke was the billionaire owner of swaths of central London, a friend of Britain's royal family and the scion of an aristocratic family stretching back to the Norman Conquest
But he told the BBC in 1995 that he had been a reluctant heir, whose childhood dream was to be a farmer.
"It was rather forced upon me," he said. When his father told him he would one day inherit the title and estates, it "almost made me run for the door, slam it and keep on running."
The Grosvenor Estate said the 64-year-old duke died Tuesday at a hospital in Preston, in northwestern England, after suddenly becoming ill at his vast Abbeystead Estate nearby.
His 25-year-old son Hugh Grosvenor — a godfather to young royal Prince George — will inherit the title and the Grosvenor Estate, which owns 300 acres (121 hectares) in some of London's wealthiest areas.
The Grosvenor family traces its roots back to the Norman invasion of England in 1066.
The Financial Times said one of its reporters once asked the duke what advice he would give to a young entrepreneur wanting to succeed. He joked: "Make sure they have an ancestor who was a very close friend of William the Conqueror."
A 17th-century ancestor, Sir Thomas Grosvenor, married heiress Mary Davies and acquired what was then marshland in 1677. Over the generations, the family developed the land into two of London's most affluent neighborhoods, Mayfair and Belgravia.
The family's property portfolio includes land across Britain, as well as housing, office and retail space around the world.
For years, the Sunday Times Rich List ranked the duke as Britain's wealthiest man, though in recent years he lost the crown to some of the world's super-rich who based themselves in the U.K. This year the newspaper estimated his wealth at 9.35 billion pounds ($12 billion).
Grosvenor inherited his title, and the family business, when his father died in 1979. In the late 1990s he had a nervous breakdown, later citing the pressures of business and public appearances.
"Given the choice, I would rather not have been born wealthy, but I never think of giving it up," he told The Independent newspaper in 1992.
He made the same point to the BBC three years later.
"It's part of my heritage," he said. "If I'm lucky I might live on this earth for 70 years. That estate has been with us for three, four, five, six hundred years. So I'm only a mere flicker in the process of time."
The duke's aristocratic clan is closely tied to British royalty. Hugh Grosvenor, who becomes the 7th duke, is one of seven godparents to Prince George, son of Prince William and his wife Kate.
Buckingham Palace said Queen Elizabeth II was sending a message of condolence to the duke's family. Prince Charles' office said he and his wife Camilla were "deeply shocked and greatly saddened" by his death.
The duke's estate said the family had asked for "privacy and understanding at this very difficult time."
The duke is survived by his wife Natalia, his son and three daughters.