Mitsuyo Seo  

Initially, Seo worked as a sign painter before moving on to draw animations at a company that made short films for home use. Although his most well-known works were propaganda films produced during World War II, he was politically leftist and had sympathies towards the Proletarian Film League of Japan. In 1931, Seo was arrested, tortured, and spent 21 days in jail for his political activities. He later met Kenzō Masaoka and joined his company, where they worked on Japan's first sound animation film. Seo then started his own production company, creating cartoons featuring the character Norakuro. In 1937, he joined Geijutsu Eigasha studio and made Ari-chan, which was the first Japanese work to fully use the multiplane camera. His most famous works are two propaganda animated films produced during World War II, Momotarō no Umiwashi and its sequel. After the war, Seo joined Nihon Manga Eigasha and made Ōsama no Shippo as a pro-democracy anime. However, when Toho found it politically too leftist, the film was left without a distributor. As a result, Nihon Manga Eigasha went bankrupt, and Seo left the industry to become an illustrator for children's books due to the difficult conditions for animation in the immediate post-war period.