Oooohh.. have to pull you up on that one dear.. it's actually an Irish/Scottish EXPORT ! We gave Guising to America. We used to carve turnips.. but being Americans turnips were in short supply they used pumpkins.
Halloween.. The Hallowed Eve is/was an important spiritual festival in celtic lands.
yes, trick or treating is very much American.. but going round doors singing a song, telling a joke or doing another party piece in return for apples, sweets etc is very much from this side of the Atlantic.
sorry
EDIT Gav beat me
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