Kaspar Hauser
The boy was taken to an army captain whose name was Wessenig. The only things Kaspar could say (in German) were: "I want to be a knight, as my father was," and "Horse! Horse!" The captain asked him lots of other questions but the boy only cried and said "Don't know."  He was taken to a police station where he could only write his name: Kaspar Hauser.