dylan got sued by dimminic behan for stealing the tune of "the patriot game" for his "with god on our side"

within reason i think it's folk porocess but if you "borrow" another song writers originnal tune then you should acknowwledge it.

i just heard "the banks of newfoundland" to the tune of "the lakes of ponchartrain", a very nice version.

the nova scotia version of fennario has a totally different tune and it's called "bonnie barbry o" as does the nova scotia version of "barbra alan" totally different tune. you can find both either in helen creighton or the canadian government folk song collection from the sixties(i have a cd reissue but can't remember the title"

so sometimes old words have new tunes.

i suspect the tunes are scottish, however as helen creughton collected a lot of those from the guysborough and halifax county shores where there were a lot more scotts immigrants than english.