Mari Lwyd

The Mari Lwyd tradition was once carried out in South Wales. Groups of men would go around door-to-door with a horse prop, made of a horse skull on a stick, asking for entry to the house in a song. The homeowners would deny entrance through a song, and it would go back and forth until someone eventually gave up. If the homeowner gave up first, the group of men would be granted access to their home and would be allowed food and drink and to basically cause chaos in the house.

Source: emgn.com