When genres melded...

At some point rock, hard rock indeed, developed a sensibility that included aspects of both UK folk and Americana; perhaps not both at the same time and almost certainly not in the same place.
That would probably be in the early 1970s and this is one of the albums that, I believe, was a trail-blazer although the band in question were actually heading in the direction of harder rock at that time.

This is Decca SKL 5170 (1973) and hard rock it is not!  It is still very good though...

Eric Bell was a victim of the changes but perhaps its time has come around again.  A bonus is that SKL 5170 came with an illustrated lyric sheet.
Even in later Thin Lizzy albums this traît was evident - Jailbreak (1976) is a very good example.  It was, on the face of it, a 'full-on' hard rock album but the subject matter was actually rather traditional...  It was also the album that finally saw them see some success in the US.