sentences:  Ising focused on the "Barney Bear" cartoons, while Harman focused on making intricately animated one-shot cartoons, although Harman was able to establish a short-lived series of "Three Bears" cartoons.At this time, Harman created his masterwork, "Peace on Earth".Released during the holiday season of 1939 (immediately after the outbreak of World War II in Europe), "Peace on Earth" was a serious work which dealt with the idea of what a post-apocalyptic world would be like.