IT WAS worth the wait. Fifteen years after she began writing her magisterial biography of Henri Matisse, the French artist, Hilary Spurling saw her labour of love win one of Britain’s leading literary awards.

The 65-year-old author followed in the footsteps of the poets Ted Hughes and Seamus Heaney, among previous winners, when she picked up a cheque for £30,000 at an awards ceremony attended by almost 500 publishers, agents and authors.

The judges — who included the actress Emilia Fox and the novelist Margaret Drabble, under the chairmanship of the former Children’s Laureate Michael Morpurgo — defied expectations.

Ali Smith’s novel The Accidental, the story of a family whose lives are turned upside down by a mysterious stranger, had been the odds-on favourite. But it did not even feature in the judges’ heated debate.

Emerging from a fraught session that lasted almost two hours, they described Matisse the Master as a “masterpiece”.

They said that it had been a three-book race and that neither The Accidental nor The Harmony Silk Factory, a debut novel by Tash Aw, was in it.

Instead it was between Kate Thompson’s children’s novel, The New Policeman, and Christopher Logue’s Cold Calls, the fifth instalment of his contemporary account of the Iliad.

The judges applauded Thompson’s “extraordinary evocation of place” and her dialogue and Logue’s powerful use of language. It was so close that votes had to be cast.

Mr Morpurgo said: “I’ve never been on a judging panel which was as close. There was no blood on the carpet but it was very heated.” Eventually the judges picked their winner, saying that Spurling “had made us see Matisse in a new light”.

Mr Morpurgo said that she had produced a massive work — but one that “didn’t read like it”.

“It reads like a story . . . she somehow managed to paint a picture of a painter which was accessible to people who are not necessarily familiar with his art. That’s an extraordinary achievement.”

Spurling. who was born in Stockport in 1940, was a theatre critic and literary editor for The Spectator. She is a regular reviewer for the national press and has written biographies of Ivy Compton-Burnett and Paul Scott, among others.

When she embarked on her study she was astonished that no one had written a biography of Matisse in the 50 years since the artist’s death.

She overturned half-truths and misconceptions that had arisen about him, such as the assumption that he automatically slept with his models, and was given unprecedented access to the painter’s family correspondence.

Matisse wrote regularly to his wife, sending letters that amounted to a detailed daily journal, whenever the couple were separated, and also wrote to other members of his family. Through his accounts, she painted a portrait of a life of desperation and self-doubt.

Her win was widely welcomed last night. Rodney Troubridge, fiction buyer for Waterstone’s, said: “Spurling is an extremely good biographer and her long list of works holds testimony to the quality of her work.

“Matisse the Master is yet another glorious example of her fine writing style and I am thrilled that her work has been recognised in this way.”

Whitbread will stop its £300,000 sponsorship of the prize this year, ending a tradition going back to 1971 when it was established to reward “enjoyable books” by writers based in Britain and Ireland and as a rival to the Booker Prize. Negotiations are under way with possible sponsors.

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