Songfacts®:

• The words to this carol were written by Irish hymnist, lyricist and third English Poet Laureate Nahum Tate, who was otherwise best known for reviving Shakespeare's King Lear in order to give it a happy ending. He based them on the Gospel of Luke 2:8-14. The exact date of Tate's composition is not known, but the words appeared in Tate and Nicholas Brady's 1700 supplement to their New Version of the Psalms of David of 1696.
• This was the first carol to cross over from secular traditions to the church in Britain. It was the only Christmas hymn authorized to be sung by the Anglican Church in the first half of the 18th century. Other carols, were considered too secular for inclusion in church services because of their folk roots, and were not sung in churches until the end of the 18th century.
• The tune used in most church services today is only one of a number of variations played over the carol's 300-year history. The current tune used most commonly in Canada and the United Kingdom uses the music "Winchester Old", originally from Este's psalter, the Whole Book of Psalmes, from 1592 but arranged by William Henry Monk sometime before 1874. It only became widely popular as the base for the carol after the 1861 publication of the Church of England's Hymns Ancient and Modern. Before that the tune "Cranbrook" by Canterbury shoe-maker Thomas Clark – better known as "On Ilkla Moor Baht 'at "– was the preferred version across much of the country. That version is still sung in some Yorkshire pubs.
• In the USA, the most commonly used version is David Weyman's adaptation of "Christmas." This was taken from an aria in the 1728 opera Siroe by George Frideric Handel, as arranged by prominent American music educator, music editor, and hymn writer Lowell Mason in 1821.