Carol singing

The tradition of wassailing (alt sp wasselling) falls into two distinct categories: The house-visiting wassail and the orchard-visiting wassail. The house-visiting wassail is the practice of people going door-to-door, singing and offering a drink from the wassail bowl in exchange for gifts. This practice still exists, but has largely been displaced by caroling. The orchard-visiting wassail refers to the ancient custom of visiting orchards in cider-producing regions of England, reciting incantations and singing to the trees to promote a good harvest for the coming year.

The word wassail comes from the Anglo-Saxon greeting Wæs þu hæl, meaning "be thou hale"—i.e., “be in good health”. The correct response to the greeting is Drinc hæl. According to the Oxford English Dictionary waes hael is the Middle English (and hence post-Norman) spelling parallel to OE hál wes þú, and was a greeting not a toast.

The American Heritage Dictionary, fifth edition, gives Old Norse ves heill as the source of Middle English waeshaeil. However the Oxford English Dictionary explicitly rejects this, saying "neither in Old English nor in Old Norse, nor indeed in any Germanic language, has any trace been found of the use as drinking formulas".

Later, in the twelfth century, Danish-speaking inhabitants of England turned "was hail", and the reply "drink hail", into a drinking formula, a toast, adopted widely by the indigenous population of England. In recent times, the toast has come to be synonymous with Christmas.

Traditionally, the wassail is celebrated on Twelfth Night (variously on either January 5 or 6). Some people still wassail on "Old Twelvey Night", January 17, as it would have been before the introduction of the Gregorian Calendar in 1752.

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Wikipedia