He was responsible for the distinctive style of the earliest Disney animated cartoons, and was also responsible for designing Mickey Mouse. In 1922, when Disney began his Laugh-O-Gram cartoon series, Iwerks joined him as chief animator. The studio went bankrupt, however, and in 1923 Iwerks followed Disney's move to Los Angeles to work on a new series of cartoons known as “the Alice Comedies” which had live-action mixed with animation. After the end of this series, Disney asked Iwerks to design a character that became Oswald the Lucky Rabbit. The first cartoon Oswald starred in was animated entirely by Iwerks. Following the first cartoon, Oswald was redesigned on the insistence of Oswald's owner and the distributor of the cartoons, Universal Pictures. The production company at the time, Winkler Pictures, gave additional input on the character's design.