KUSA - Sure, everyone knows Halloween is about dressing up and giving out candy, but does anyone know the origin of the holiday?
It's believed to have started by the ancient Celtic festival of Samhain - when spirits were thought to roam the Earth on their way to the afterlife.
Some spirits were not so friendly and would play tricks on the living, so to confuse them, people would dress up in costumes. And to keep the spirits happy, the living would leave out food and drinks.
Later on, people started going house to house in costume - offering to perform their own tricks for some fabulous treats.
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