Saiyuuki

Alakazam is a young and brave monkey who convinces all the other monkeys to make him their king. After attaining the throne and learning magic, he becomes so vain that he goes to heaven to challenge the gods. He is defeated by King Amo, and sentenced to serve as the bodyguard of Prince Amat in order to learn humility. Osamu Tezuka was named as a director of the film by Toei Company. However, Tezuka later stated that the only time he was in the studio was to pose for publicity photos. His involvement in promoting the film, however, led to his interest in animation.

(Source: AniList.co)