 Willems is said to have copied it from several one-sheet prints sold by market singers and before that the song was passed along orally.The nature of the story itself dates it back to the early Middle Ages, yet it contains several elements of Carolingian culture and therefore is generally accepted to be much older than the comparable Lady Isabel and the Elf Knight.Since the ballad was passed along for centuries, it has been updated and changed all over its life and some verses may have even been added centuries after its original inception.