James Hilton (novelist) picked "Lost Horizon" as its first title in 1939. For that reason, the novel is frequently called the book that began the "paperback revolution." Hilton is said to have been inspired to write "Lost Horizon", and to invent "Shangri-La" by reading the "National Geographic Magazine" articles of Joseph Rock, an Austrian-American botanist and ethnologist exploring the southwestern Chinese provinces and Tibetan borderlands. Still living in Britain at the time, Hilton was perhaps influenced by the Tibetan travel articles of early travellers in Tibet whose writings were found in the British Library. Christian Zeeman, the Danish father of the mathematician Christopher
What Was Lost Was Lost" was the winner in the first novel category of the Costa Book Awards. O'Flynn received a £5,000 prize. It was short-listed for the overall Costa Book of the Year Award. The Costa Book Awards' judging panel, chaired by Joanna Trollope, praised the novel for "blending humour and pathos in a cleverly constructed and absorbing mystery." They described the novel as inventive, compelling, and poignant. "What Was Lost" was long-listed for the 2007 Man Booker Prize and the Orange Prize for Fiction. It was short-listed for the Guardian First Book Award. It won the Jelf Group First Novel Award