I'm intrigued by a lot of the other references in this song as well. For example, who is "John DeGroot" and what does the "reckless stain of Cairn" refer to? Possibly someone who killed or betrayed his brother, hence a biblical reference to Cain & Able?

And is there really such a place as "Urquart's fairy glen, where the little people are known to dance? Hah, it certainly all sounds like traveler lore to me.