There is a song in the Digital Tradition database, which, the notes say, dates from the 17th century, and which describes how the twelve days of Christmas were celebrated back then. Clicking here will lead you right to it.

Singing and partying, putting on pageants and pantomimes (and other activities of a more ribald nature) seems to be the gist.

I seem to remember reading somewhere (but I can't find it after a quick search of where I thought I'd read it -- maybe I heard it on a PBS documentary, or something) that the tradition of staying home in the bosom of your family -- behind closed doors -- began in the Victorian era, when the idea of members of the working classes going from door to door, singing loudly and demanding drink and money (as in the Gloucestershire Wassail) was a threat to the rising middle class. As I understand it, it was then that the extravengance of Christmas was turned from activities (singing, dancing, eating, etc.) to material goods. No doubt the merchant class, who made up a good portion of the aforementioned middle classes, had a lot to do with that.

Personally, I wish the tradition of visiting neighbors on Christmas would come back, and live singing, rather than having a christmas record playing as 'background music.'

But I use a wheelchair, and can't get to any of my neighbors' doors to ring the doorbell myself, or I would -- with a song in my throat and my arms ready to hug.... Oh well...