Music is a big part of Christmas, which makes the season sort of strange among holidays. Other holidays don't have so many songs that radio stations can play them 24/7 for a month! Christmas began to have its own music in the fourth century, but those songs were ordained by the church, sung in Latin, and no one much liked them as they were more doctrinal than festive.
The man who freed the Christmas carol from this prison of poor taste was St. Francis of Assisi, one of the church’s gentlest but most crucial reformers. In the 13th century, Francis tried to break the Christmas celebration from its tedious husk, mostly by making the birth of Christ into a live theatrical event. He organized nativity pageants featuring real hay, real animals, and, for the first time, real music: Deviating from tradition, he allowed for narrative songs in audiences’ native languages, turning Christmas music into an opportunity for mainstream creativity. Drinking songs were given Yuletide lyrics (greatly to the church’s horror) and disseminated by traveling entertainers. Christmas began to take on a life of its own, beyond the exigencies of the sacred feast.
But things took a dim turn with the Puritans in the 1600s. Read the rest of the evolution of the Christmas carol at Slate. Link
(Image credit: Robert Neubecker)