Oswald was first introduced in a 1927 cartoon called "Trolley Troubles", written and drawn by Walt Disney and Ub Iwerks for Charles Mintz of Universal Studios. The series was successful, but when Disney and Iwerks asked for a higher budget, Mintz fired them and hired Walter Lantz to produce new cartoons using the character. Disney and Iwerks went on to found the Disney Studios and create a new character originally similar to their version of Oswald, called Mickey Mouse.