I never tire of saying that I believe it very unwise to attempt to date such songs as this only as far back as our knowledge of folk songs, which basically is to the beginning of the twentieth century - anything we know, or think we know predating that is far to circumstantial to even base a guess on, let alone made definitive statements and claims. The practice of arranged marriage almost certainly pre - dates reliable recorded history and continued uninterrupted almost to the present day in these islands - it is likely that it still occurs in some communities - we have certainly witnessed and recorded evidence of it.
Ireland's first falling into the hands of a foreign power in 1169 was consummated by an arranged marriage.
Versions of songs are pretty much like a photographs of running horses - we have no idea where their journeys began nor what point of they had reached when the shot was taken.
The song presents no information, not even a name; the ages are totally immaterial.
Print is no indication, particularly at a time when literacy meant little for the overwhelming majority of the population, particularly among those from the class where these songs proliferated.
Rather than speculating on not very coincidental 'coincidences', it is far safer to assume that songs like this are links in a very long chain from an unknown foundry - songmaking has been around far too long to assume otherwise.
As an old singer told us a couple of years ago "if a man farted in church, somebody made a song about it.
Sorry to bang on about this - waiting for some soundfiles to load down.
Jim Carroll