On the first Chirstmas Eve, nearly two thousand years ago, the hills around Bethlehem echoed with song. Sleepy shepherds learned of Jesus' birth from angels singing praises to God and journeyed, amazed, to visit the infant in the manger. As they walked back to their flocks the shepherds, too, sang songs of rejoicing.
The Victorians loved music so it is no surprise that they revived the old medieval carols and also composed new ones, both secular and religious.
Full Article: Christmas Carols and the Victorian Era