The Mari Lwyd is a Welsh tradition in which a group of people carry a horse skull mounted on a pole — draped in a white sheet with the operator hidden underneath — to your door at Christmas and demand entry through song.
You are expected to refuse, also through song.
What follows is essentially a medieval rap battle: the Mari Lwyd party sings their case for why they should be let in, you sing back why they shouldn't, and this continues until someone runs out of verses. If you lose, the skeletal horse and its entourage get to come inside, and you have to give them food and drink. 10
The tradition dates back to at least 1800, and the groups typically included the horse carrier, a leader, and people dressed as stock characters like Punch and Judy. Folklorists have debated whether "Mari Lw

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