The book, published in Britain by Chatto & Windus, centers around the deeply religious 10-year-old Judith McPherson, who with her father belongs to a religious sect and who is scorned and bullied at school.

She seeks to build a better, albeit imaginary world, of model figures and papier-mache mountains in the privacy of her bedroom, and when she performs her first miracle, her troubles really begin.

According to the prize's administrators, the story is partly based on the author's own experiences as a girl brought up in a Christian sect in Wales who was removed from school at the age of 10.

She, like her main character, also developed her own secret world in miniature, and, after re-entering school was encouraged to apply for university. She went on to read English Literature at Oxford.

"The Land of Decoration is a novel that can move the reader from sadness to laughter with alarming suddenness," said Sam Llewellyn, chair of the judges and himself first published by the late literary agent Elliott after whom the award is named.

"Grace McCleen's voice sparkles with imagery and ideas, and she uses it to tell a story that is simultaneously multi-layered and absolutely compelling."

Although the "Land of Decoration" was McCleen's first novel to be published, she had already written two other books, "The Professor of Poetry" and "The Offering", by the time it appeared in print.

"When the next novels appear I think people will have trouble knowing what to make of me because they are so different in style to 'The Land of Decoration,'" she said on her website.

"But then 'The Land of Decoration' itself has divided readers, some thinking it is deep and fantastical, and others so basic a child could have written it. Perhaps the more misunderstanding the merrier.

"I have just finished my fifth novel (fourth that will be published) and the last I will write. I would like to concentrate on music from now on, which I would love to have pursued when I was younger."

Now in her early 30s, McCleen expects her last novel to be published in 2015, and has said publicly that she will not miss writing once she gives it up.

The author beat two other shortlisted writers to claim the 10,000 pound ($16,000) Desmond Elliott Prize.

Patrick McGuinness' "The Last Hundred Days" was inspired by his years in Bucharest in the runup to the Romanian revolution and Rachel Joyce's "The Unlikely Pilgrimage of Harold Fry" was originally drafted as a radio play for her dying father.

(Reporting by Mike Collett-White; editing by Patricia Reaney)

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