Iron John

"Iron John" (AKA "Iron Hans" or "Der Eisenhans") is a German fairy tale found in the collections of the Brothers Grimm, tale number 136, about a wild iron-skinned man and a female prince (The original German title is Eisenhans, a compound of Eisen "iron" and Hans, like English John a common short form of the personal name Johannes). It represents Aarne-Thompson type 502, "The wild man as a helper".