Short films by Studio Ghibli
Studio Ghibli is a Japanese animation film studio founded in 1985. In addition to producing 18 feature films, the studio has produced several short films, including commercials, films for the Ghibli Museum, music videos, and works released directly to video.
Shinchosha
Grave of the Fireflies is the first Studio Ghibli film that Disney never had distribution rights to in North America, since the film was not produced by parent company Tokuma Shoten (though Disney handles North American distribution of all Tokuma Shoten-produced Studio Ghibli films) but by Shinchosha, the publisher of the original short story (as mentioned; although Disney has the Japanese distribution rights themselves).