How old is the song Deck the Halls?

Answer 1

The music to Deck the Halls is believed to Welsh in origin and was reputed to have come from a tune called "Nos Galan" dating back to the sixteenth century. In the eighteenth century Mozart used the tune to Deck the Halls for a violin and piano duet J.P. McCaskey is sometimes credited with the lyrics of Deck the Halls but he only edited the Franklin Square Song Collection in which the lyrics were first published. The first publication date of Deck the Halls is 1881. The author is unknown but the words are said to originate in America.

So, 1881.