In 2006 he published his first novel, Hestekrefter, which was a bestseller throughout Scandinavia. In 2010, The Wood Book. A Life in the Forest (Alfaguara, 2016) sold more than 300,000 copies in Sweden and Norway alone, and became a TV series with a large audience. In the United Kingdom he sold 100,000 copies and won the British Industry Award. His novel, The Sixteen Trees of the Somme (Alfaguara, 2017), has received the Norwegian Booksellers Prize, has been translated into twelve languages and has been broadcasted on television.