I didn't know it 'till years later, but it was the folk flavoring to much of what we now call Folk-Rock of the 70s that made that music appeal to me; also why I listen to trad rather than pop now.

Fairport, Pentangle, Traffic (John Barleycorn in particular) early Tull - then the home grown stuff here in the US that came after - early Buffalo Springfiled, early Crosby Stills & Nash (heck, even early Jefferson Airplane, though Starship's Blows Against the Empire included Rosalie Sorrell's "Baby Tree" on it)

It was the characteristics of the traditonal music that gave Folk-Rock the backbone and content and vitality that made it so delicious. I doubt I'm far from the only one who got introduced to the folk that was more traditionally flavored than the then pop PPM, Kingston Trio, etc.