One Summer of Happiness (Swedish: Hon dansade en sommar, lit. 'She danced one summer') is a 1951 Swedish film by director Arne Mattsson, based on the 1949 novel Sommardansen (The summer dance) by Per Olof Ekström. It was the first Swedish film to win the Golden Bear at the Berlin International Film Festival. It was also nominated for the Palme d'Or at the 1952 Cannes Film Festival. Today, the film is mainly known for its nude scenes, which caused much controversy at the time and, together with Ingmar Bergman's Summer with Monika (1953), spread the image of Swedish "free love" around the world.