Crowther, 40, has authored more than 30 titles, most which were first published in Belgium and France, the prize jury said. The annual 5 million kronor ($620,000) award is named after late Swedish writer Astrid Lindgren, creator of the Pippi Longstocking book series.

It was established by the Swedish government in 2002 and will be handed out by Princess Madeleine in a ceremony June 1. Crowther's principal works are picture books, including “L'enfant racine” (“The Root Child”) and “La visite de Petite Mort” (“The Visit of Little Death”).

“She maintains the tradition of the picture book while transforming and renewing it,” the jury said in its citation. “In her deeply felt empathy with people in difficulty, she shows ways in which weakness can be turned into strength. Humanism and sympathy permeate and unify her artistry.”

In an interview with the Associated Press, Crowther said she had found out she had won the award at a book fair in Bologna, Italy. “It's fantastic,” she said by phone, adding she had grown up reading Lindgren's books.