Review by Hephzibah Anderson

"Queen Elizabeth the Queen Mother: The Official Biography" is published by Macmillan in the U.K. (1,096 pages, 25 pounds). It will be published in the US in October by Knopf, under the title "The Queen Mother" ($40).

(Bloomberg) — In the latter decades of her long life, the Queen Mother became the world's favourite granny. It's an image both confirmed and complicated by William Shawcross's keenly awaited biography, which suggests that a steely core lay beneath her yards of pastel chiffon.

The 1,096-page book is being touted as the definitive study. It is also authorised: In return for granting access to the Royal Archives, the Palace has scrutinised Shawcross' work, even approving the publicity schedule.

While some mysteries inevitably endure, "Queen Elizabeth the Queen Mother: The Official Biography" paints a portrait of a remarkable life lived in step with a century of sweeping change. The ninth of the Earl of Strathmore's 10 children, Elizabeth Angela Marguerite Bowes-Lyon was born on August 4, 1900. As a young woman, she won many suitors, among them Prince Albert, second in line to the throne, who would later become King George VI.

He proposed three times before she accepted. They were wed in 1923 amid celebrations that included a nine-foot-high, 800- pound cake. When the abdication of King Edward VIII catapulted her stuttering husband onto the throne in 1936, she was genuinely afraid of what the "terrible responsibility" would do to him, later blaming her brother-in-law for shortening his life. Within three years of their coronation, the country was at war.

Refusing to flee abroad, she and the King endured bombing raids on Buckingham Palace. Not even Winston Churchill was informed of how close they came to death on one occasion.

Blitz casualties were worse in working-class areas. "I grind my teeth in rage," she declared after touring a children's hospital. When the enemy added the cruise missiles known as doodlebugs to their arsenal, she wrote a note to Princess Elizabeth "in case I get 'done in' by the Germans!" As well as explaining how her jewellery should be divided, she reminded her oldest daughter to always keep her temper and her word.

Missives like this form the book's emotional core. A prolific correspondent, Queen Elizabeth wrote letters in a clear hand and a jubilant, sometimes caustic voice, making liberal use of exclamation points and often displaying a whimsical approach to spelling. The letters conjure intimate domestic vignettes: the excitement caused by a food parcel received in 1942 from J.P. Morgan, for instance, or Prince Charles as a toddler, playing happily with a box of his grandmother's old lipsticks. They also convey her devastation at being widowed at just 51.

Though King George's death left her bereft of an official role, some of her most important work was still ahead. She marshaled the royal family through increasingly difficult times, as social change redefined its role and the press became ever more intrusive.

"Her entire life was based upon obligation, discretion and restraint" Shawcross writes, and in places, that same trinity seems to underpin his biography. Did romance spice Queen Elizabeth's half-century as a widow? He doesn't say. As for Princes Charles's divorce, Princess Margaret destroyed her mother's letters from Princess Diana, so there is little left to tell.

On the subject of Queen Elizabeth's finances, Shawcross finds it hard to contradict reports that her Coutts & Company overdraft stood at £ 4 million ($6.5 million at current exchange rates) in 1996. This was largely the result of her active racehorse habit and fondness for lavish entertaining. Thanks to the gin that flowed as readily as a Scottish brook, her parties always went with a swing. He does set a few records straight, dispelling rumours of a colostomy in 1966 and revealing that she in fact underwent successful treatment for colon cancer.

In the end, he evokes his royal subject so effectively that to pry further would seem almost improper.