As research for the novel, Gleitzman read several books about and by young people in the Holocaust, including The King of Children by Betty Jean Lifton (a biography of Janusz Korczak), Salvaged Pages: Young Writers' Diaries of The Holocaust, edited by Alexander Zapruder, The Hidden Children by Jane Marks, Words to Outlive Us: Eyewitness Accounts From the Warsaw Ghetto, edited by Michał Grynberg, Witness: Voices From The Holocaust, edited by Joshua M. Development Īlthough Once is a work of fiction, Gleitzman was inspired by the story of Janusz Korczak, the events of World War II, and Hitler's attempt to exterminate the Jewish population of Europe. In chronological order of Felix's life, the books are Once, Then, After, Soon, Maybe, Now, and Always. Once was translated into German ( Einmal) and was nominated for the 2010 Deutscher Jugendliteraturpreis it won the 2011 Katholischer Kinder- und Jugendbuchpreis.

Although Once is a work of fiction, Gleitzman was inspired by the story of Janusz Korczak, the events of World War II, and Hitler's attempt to exterminate the Jewish population of Europe. He finds a girl, who is unconscious, called Zelda in a burning house with her dead parents-he takes her with him and protects her from confronting her parents' death by telling her stories. It is about a Jewish boy named Felix who lived in Poland and is on a quest to find his book-keeper parents after he sees Nazis burning the books from a Catholic orphanage in which had stayed at for 3 years and 8 months. Once is a 2005 children's novel by Australian author Morris Gleitzman.

Once then now book series