Until her peaceful death at 101, Queen Elizabeth The Queen Mother was Britain’s turbo-granny: a pleasure-seeking ball of energy clad in pastels and pearls who loved her country, her tipple, her Corgis and who stood up for her people.

“Wouldn’t it be terrible if you’d spent all your life doing everything you were supposed to do — didn’t drink, didn’t smoke, didn’t eat things, took lots of exercise — and suddenly one day you were run over by a big red bus, and as the wheels were crunching into you, you’d say, ‘Oh my God, I could have got so drunk last night,’” she once told Princess Diana and Major Michael Parker, a member of one of her military regiments, over tea. “That’s the way you should live your life, as if tomorrow you’ll be run over by a big red bus.”

This story first appeared in the October 19, 2009 issue of WWD. Subscribe Today.

Born Elizabeth Angela Marguerite Bowes-Lyon, The Queen Mother definitely lived by example, as William Shawcross found out while researching her official biography, in bookstores Oct. 26. “She affected the lives [of], and brought pleasure to, so many millions of people,” says Shawcross over coffee at Claridge’s. “After the abdication, she saved the monarchy. She was essential in sustaining, supporting and loving [King George VI, who inherited the throne after his elder brother, Edward VIII, renounced it to marry the twice-divorced Wallis Simpson]. Without her, he would have been completely lost.”

Handpicked by Queen Elizabeth II to chronicle her mother’s life, Shawcross spent six years studying the late royal’s private correspondence and peppering family members with questions. He says he felt no pressure to whitewash his subject: “The Queen made it clear that she wanted me to write exactly what I wanted,” he says. (And, at 1,000 pages, one assumes it’s all in there.)

The Queen Mother was no saint, either. She couldn’t stomach Simpson, later the Duchess of Windsor, who had been a Nazi sympathizer and whom she referred to as “the lowest of the low.” After World War II broke out and the Duke and Duchess of Windsor returned to England from the French Riviera, The Queen Mother wrote: “I trust that she will soon return to France and STAY THERE.”

Shawcross didn’t get to go through her letters to Princess Diana, with whom she had a warm relationship (although The Queen Mother was appalled when Charles and Diana blabbed in public about their broken marriage). In 1993, the late Princess Margaret destroyed Diana’s letters to The Queen Mother “because they were so private,” writes Shawcross, adding that Diana’s mother, Frances Shand Kydd, “went straight to Kensington Palace and shredded everything she could find” after the Princess’ death in 1997.

Much like The Queen Mother herself, Shawcross’ book is juicy, but not scandalous. Which is how the author, whose father was the lead British prosecutor at the Nuremberg War Crimes Tribunal, intended it. “It’s not a book of gossip, but a piece of history,” he says. “I wanted to put The Queen Mother in the context of an astonishing and brutal century that began with horses and carts and ended with the Concorde.”