1840, from German Rumpelstilzchen. The German form of the name is used in English from 1828.
A fairy tale from the collection of the brothers Grimm. The title character, a dwarf, tells a woman who has promised him her first-born child that he will not hold her to her promise if she can guess his name. She finds it out, and Rumpelstiltskin, furious, destroys himself.