In the Scottish version I know, it's "Howe of Auchterless", not town or glen, which is I believe geographically accurate.
From all the stuff I've done on old fiddle tune books(published and manuscript), I have to say that the earliest versions of the tune I've come across were called "Pretty Peggy of Derby", no references to Fyvie or Fernario till much much later. But equally well, I would have to say that I've done more work on English fiddle notebooks than I have on Scottish. It is notoriously difficult(in fact normally impossible) to track down "original" versions of old songs. All you can do is come up with the earliest known version, and that only lasts as a theory till someone finds an earlier one.
   As is often the case, we have an anonymous GUEST on the thread claiming the original version is Irish. Well, that's as maybe, but he or she omitted to provide any references, so that red herring is best ignored for the moment. I see no reason why it shouldnt be Irish, and no reason why it should.