Ub Iwerks (March 24, 1901 – July 7, 1971) was an American animator, cartoonist, character designer, inventor, and special effects technician, who designed Oswald the Lucky Rabbitand Mickey Mouse. Iwerks produced alongside Walt Disney and won numerous awards, including multiple Academy Awards.

Iwerks was considered by many to be Walt Disney's oldest friend and spent most of his career with Disney. The two met in 1919 while working for the Pesmen-Rubin Art Studio in Kansas City, and would eventually start their own commercial art business together. Disney and Iwerks then found work as illustrators for the Kansas City Slide Newspaper Company (which would later be named The Kansas City Film Ad Company). While working for the Kansas City Film Ad Company, Disney decided to take up work in animation, and Iwerks soon joined him.

In 1925, Hugh Harman drew some sketches of mice around a photograph of Walt Disney. Then, on a train ride back from a failed business meeting, Walt Disney came up with the original sketch for the character that would eventually be called Mickey Mouse. Afterwards, Disney took the sketch to Iwerks. In turn, he drew a more clean-cut and refined version of Mickey, but one that still followed the original sketch.

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