It is a haunting and triumphant testimony of human endurance. Young Jewish girl escapes the Nazis and treks 1,900 miles in search of her parents — living with a pack of wolves along the way. It is also entirely fictitious.

Now, Misha Defonesca, the Belgian author and subject of Misha: A Mémoire of the Holocaust Years, has been ordered to pay £13.3m back to her publisher.

Ms Defonesca, 76, and her ghostwriter Vera Lee, who both live in the US, won global fame in 1997 when the book was first published. It was translated into 18 languages, and made into a film.

In 2002, the pair won a £19m copyright claim against their publisher, Mt Ivy Press, for unpaid royalties. Mt Ivy founder Jane Daniel went on to appeal the ruling, and to conduct her own research, discovering Ms Defonseca’s date and place of birth, her real name — Monique de Wael — and that rather than “running with the wolf pack”, she was “enrolled in a Brussels school in 1943”. After a long legal battle with Mt Ivy Press, a judge this week found against Ms Defonseca.