The Frog-King, or Iron Henry
Jacob and Wilhelm Grimm,
Der Froschkönig oder der eiserne Heinrich,
Kinder- und Hausmärchen, no. 1.
Translated by D. L. Ashliman.
The Grimms' source: Not known precisely, but apparently from an oral tradition of the family Wild in Kassel. (Wilhelm Grimm married a member of this family, Dortchen Wild.)
A version of this tale was included in the Grimms' manuscript collection of 1810. From the first (1812) to the last (1857) editions published during the Grimms' lifetime, "The Frog King" has always been number one in their folktale collection.
The first edition of the Grimms' Kinder- und Hausmärchen (vol. 2, 1815, no. 13) included a variation of this story entitled The Frog Prince (in German, Der Froschprinz). This tale was not included in later editions and has thus remained relatively unknown.
Aarne-Thompson type 440.