The first Japanese feature-length animated film. It was directed by Mitsuyo Seo, who was ordered to make a propaganda film for the war by the Japanese Naval Ministry. Shochiku Moving Picture Laboratory shot the 74-minute film in 1944 and screened it on April 12, 1945. It is a sequel to Momotarō no Umiwashi, a 37-minute film released in 1943 by the same director. It is black and white. The whole movie also depicts the Japanese "liberation of Asia", as proclaimed by the Government at the time. Seo tried to give dreams to children, as well as to instill the hope for peace, with hidden movie's hints of dreams and hopes, under the appearance of war propaganda.

《桃太郎：海之神兵》是日本历史上第一部动画长片，制作于1943年，濑尾光世执导，该片于1945年4月12日对外公映，其中使用的在当时看来高水准的制作技术，成为手冢治虫制作第一部日本国产TV动画《铁臂阿童木》的基础。

讲述日本小男孩从上学到参军，在南太平洋上和日本“敌人”作战的故事

A la veille d'une mission pendant la guerre du Pacifique, un groupe de parachutistes de la marine japonaise composé d'un singe, un chien, un faisan et un ours, rentrent chez eux pour une brève visite avant de rejoindre leur base dans le Pacifique Sud. Dirigé par le guerrier Momotaro, l'escadron se prépare à attaquer l'ennemi sur Devil's Island...

Alla fine del loro addestramento navale, un orsetto, una scimmia, un fagiano e un cagnolino vanno a salutare le loro famiglie. Il fratellino della scimmia cade in un fiume e viene salvato prima di precipitare in una cascata. Successivamente, l’esercito giapponese costruisce una base aerea con l’aiuto degli animali del bosco. Un giorno, arriva con un aereo Momotaro, generale dell’esercito, accompagnato dai quattro amici, diventati oramai alti ufficiali…