 His involvement with ballet was at its greatest in the period 1938–1944, between the Spanish Civil War and the Second World War.Dalí claimed in 1974, that he had created 28 ballets, and according to Fleur Cowles, he contributed to more than 20 ballets, although most had little success and resulted in financial loss.Some of the ballets include "Tristán Loco" (with two versions, one in 1938 and the other in 1944) and the trilogy "Bacanal-Laberinto-Sacrificio" (1939–1941), on which he collaborated with Léonide Massine (a principal dancer and choreographer in the Ballets Russes).