The Grimm’s Fairy Tales, first published in German in 1812 as Kinder- und Hausmärchen, is considered to be one of the major works of 19th-century culture. Popular myth holds that the tales came from simple, peasant folk interviewed by the brothers, Jakob and Wilhelm. In reality, the bulk of the tales came from a handful of middle- and upper-class women. Most of the tales were from other origin, not German. Furthermore, the tales were heavily revised and rewritten by the Grimm brothers before publication.
In his 1983 book One Fairy Story Too Many: The Brothers Grimm and their Tales John Ellis argued that the Grimm Brothers engaged in a kind of literary fraud. As Ellis put it, “the Grimms deliberately made false claims for their tales and suppressed the evidence of their actual origin.”
Most scholars, however, are more kind to the Grimms. They agree that the tales did not come from peasant folk, but argue that the Grimms did not try to hide or misrepresent their sources. They attribute the Grimm’s revision of the tales to their attempt to synthesize different versions of the tales together.
source – hoax museum