I've added a link in the first message above (here, too) to a previous discussion of the meaning and history of this song, where Zorro contended it was a secret code used for Roman Catholic religious instruction during the period when papism was repressed in England. Interestingly, the Jesuit priest who helps out at our parish on weekends had used the same story as the basis for a sermon. I posted a message to that effect which appeared to corroborate Zorro's contention.

I think there's need for further study. Our visiting Jesuit is delightful storyteller, but one could question the scholarship of some of his research. He wasn't doing scholarly work, so it's not fair to ask that question. He found a good story, and used it skillfully to make his point.
I don't really know, but I have a hunch that the information Zorro presented could be what we used to call "old nuns' tales" when I was in the seminary - Catholic "urban legends," if you will. Back in the "good old days" in Catholic schools, the nuns used to tell us all sorts of pious stories, and I guess I have to say that some of them were a bit warped. I don't really know if the nuns believed the stories they told. As we grew older, most of us figured out that the stories just weren't true. Some of us - the ones who stayed in the Catholic Church, I suppose - find a lot of humor in this body of legends. Others look on the telling of these stories to children as a horrible thing that can warp children forever - and I suppose that most of these people left the church with a bitterness that will never be cured. And I suppose there are others, still pious Catholics, who believe all those stories.
I have to say that I was a bit distressed when my son came home from second grade with a story I had heard as a kid, about the robbers who stole consecrated hosts from a church, and then the robbers stabbed the hosts with a knife and the hosts started bleeding, and left a trail of blood so the priests could track down the robbers and rescue the hosts. Well, heck, it is a great story, but my son is now 26 and has a horrible attitude about the Catholic Church, so maybe it wasn't a good idea to tell those stories.

So, is Zorro's explanation of the 12 days an old nun's tale? I dunno. I suppose the same question could be asked about the contention that "Green Grow the Rushes" was a catechetical device. I'm sure that both songs have been used for religious teaching. That's exactly what our parish Jesuit did - but is that their origin? It's an interesting question, I think.
This is one of those situations when I'd like to hear an opinion from Bruce Olson.
Bruce?
-Joe Offer-