I've noticed a lot of more modern songs (though not really folk, per se) that allude to literary characters, themes, ideas, settings, etc. In addition to folk, I listen to (shamefully) a lot of heavy metal and glam. The books I've noticed being used in those genres are the Cthulhu Mythos books by H.P. Lovecraft (who is one of my favorite authors).

I was wondering, does this idea of using literature as a basis for songs exist in folk music? If so, then to what extent?

I imagine not in traditional folk music--which is what I am most familiar with--but what about modern folk and classic rock? What other genres of music does this exist in?

Peace--Keli