Midwestern U.S.. Also called callithump parade. a children's mummer's parade, as on the Fourth of July, with prizes for the best costumes.
Origin of callithump
1855-60, Americanism; compare earlier callithumpian band assembly of noisemakers on New Year's Eve, British dialectgallithumpians disturbers of order at Parliamentary elections, probably equivalent to dial. gally to frighten (as in gallicrow scarecrow; akin to Old Englishagælwan to scare) + thump + -ian