I got my information from a book I picked up from the local library: From Enchanted Forests to the Modern World by Jack Zipes (1988), especially the first chapter, which was based on a speach Zipes gave at some university or other, iirc.

I just checked Amazon for the listing here, and saw that it is currently out of print, but is planned to be reissued as a second edition in both hardcover and paperback in December of this year.

They were philogists who collected fairy tales to study language shifts, but they first got interested in those language shifts when they started studying the history of German law -- how the then near-fuedal system of German city states got encoded into law, and, more important, how they might get out of that system...

A bit like our discussion of "sea-guinea-rabbit-pig" in this thread (i.e. "This is what the wording of law X means now, but what did this wording mean when law X was first thought up?"). It didn't take long for them to realize that studying the language and the stories that language was a lot more interesting than law, and not just more interesting to them, but also "civilians". o they shifted their focus to the stories fairly early... (I think they made a good call on that one ;-))

But they did start out studying law...