As Christianity spread, elements of Samhain merged with Christian celebrations, particularly All Hallows’ Eve, the night before
All Saints’ Day. This blending encouraged people to dress as saints, angels, or demons, further shaping the modern Halloween costume tradition
. By the 19th century, Irish and Scottish immigrants brought these customs to America, where Halloween began to evolve into a community celebration. The late 19th and early 20th centuries saw a rise in elaborate costumes influenced by popular culture, with companies beginning to mass-produce costumes for children and adults alike.
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