how is mickey mouse related to him?
Along with Iwerks he developed Mickey Mouse.
Walt Disney
To replace Oswald, Disney and Iwerks developed Mickey Mouse, possibly inspired by a pet mouse that Disney had adopted while working in his Laugh-O-Gram studio, although the origins of the character are unclear. 
disney animation from 1940 with a classical music sound track Fantasia who produced the film? Walt Disney what is the film about? UNANSWERABLE where is the producer mentioned above from? Hermosa, Chicago when did he start his career? 1920 what are some of the awards conferred to him? Thailand's Order of the Crown, Germany's Order of Merit, Brazil's Order of the Southern Cross and Mexico's Order of the Aztec Eagle. when did he die? December 15, 1966 what was the reason for his death? Circulatory collapse caused by the cancer.
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Walt Disney [SEP] Creation of Mickey Mouse to the first Academy Awards: 1928–1933
To replace Oswald, Disney and Iwerks developed Mickey Mouse, possibly inspired by a pet mouse that Disney had adopted while working in his Laugh-O-Gram studio, although the origins of the character are unclear. Disney's original choice of name was Mortimer Mouse, but Lillian thought it too pompous, and suggested Mickey instead. Iwerks revised Disney's provisional sketches to make the character easier to animate. Disney, who had begun to distance himself from the animation process, provided Mickey's voice until 1947. In the words of one Disney employee, "Ub designed Mickey's physical appearance, but Walt gave him his soul." Mickey Mouse first appeared in May 1928 as a single test screening of the short "Plane Crazy", but it, and the second feature, "The Gallopin' Gaucho", failed to find a distributor.