Dalí's most frequent subjects, apart from the world of dreams, are those of intoxication, fever and religion; his wife Gala is often depicted in his paintings. Dalí's sympathy for the Spanish dictator Francisco Franco, his eccentric behaviour and his late work often led to controversies in the evaluation of his person and his works up to the present day. Dalí was born in Figueres, Catalonia, and received his fine arts training in Madrid. Influenced by Impressionism and the Renaissance masters from a young age, he was increasingly drawn to Cubism and avant-garde movements. In the late 1920s he moved closer to Surrealism and in 1929 joined the Surrealist group, soon becoming one of its leading exponents. His most famous work, The Persistence of Memory, was completed in August 1931 and is one of the most famous Surrealist paintings. Dalí lived in France during the Spanish Civil War (1936 to 1939) before moving to the USA in 1940, where he achieved commercial success. He returned to Spain in 1948, where he announced his return to the Catholic faith and developed his style of "nuclear mysticism" based on his interest in classicism, mysticism and recent scientific developments.