Tom and Jerry
"The Yankee Doodle Mouse" and "The Lonesome Mouse" make WWII references.
MGM Oneshots
"War Dogs", "The Stork's Holiday", "Innertube Antics" as well as Barney Bear's wartime shorts "The Rookie Bear", "Bear Raid Warden" and "Barney Bear's Victory Garden" were MGM's only wartime shorts.
Tex Avery
Walter Lantz
"Boogie Woogie Bugle Boy of Company B", "Andy Panda's Victory Garden", "Ration Bored", "Woody Dines Out", and "The Enemy Bacteria" are several of Walter Lantz cartoons.
Columbia Cartoons
The most popular wartime short by Columbia Cartoons is "Song of Victory".
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"Momotarou's Divine Sea Warriors", "The Yolk's on Me", "Little Orphan Annie", "Nimbus Livere" are other examples of wartime cartoons.