Talk:Into the Schwarzwald/@comment-34844773-20180324224529/@comment-25862208-20180324232254

According to canon from the show, the term "Grimm" became more common by the mid-1800s and is believed to have come from the Brothers Grimm, but there are some Grimm diary entries that show that the term could've had earlier origins. One example is one Grimm that is known only as "H. Grimm" writing an entry about Faeteo fatalis. There's the possibility that the term is a family name and that at some point between the first century and the Fourth Crusade, at least among Grimms, the term started to come into use. The Endezeichen Grimms appear to have been some sect of the early Grimms, as most Wesen believe they died out, and they were known for branding the "G" symbol, so I would suspect the term was being used at that time.

In all likelihood though, you're correct, the term Grimm is older than the Brothers, but they made it much more common.