Karl Wilhelm Naundorff (1785? – August 10, 1845) was a German clock- and watch-maker who until his death claimed to be Prince Louis-Charles, or Louis XVII of France. Naundorff was one of the more stubborn of more than thirty men who claimed to be Louis XVII.
Prince Louis-Charles, the son of Louis XVI and Marie Antoinette, was imprisoned during the French Revolution and believed to have died in prison. However, there were various rumors that monarchist sympathizers had spirited the young dauphin away from the Temple prison and that he was living elsewhere in secret.
The first records of Karl Wilhelm Naundorff are from 1810 in Spandau, Berlin, where he received the citizenship of Prussia. By 1822 he had moved to live with a family in Brandenburg-on-the-Havel where he was later accused of arson and 1824 was jailed for three years for counterfeiting.
When he was released in 1827, he moved to Crossen and wrote the first of two books of would-be-memoirs. The second he wrote in England many years later and was translated to English by Charles G. Perceval, Rector of Calverton, Buckinghamshire, and nephew of Spencer Perceval. He claimed that he had been substituted with a deaf and mute orphan who died soon afterward and that he had been hidden in a secret area of the Tower of the Temple until his escape. He also claimed that he was later recaptured by Napoleon's forces and secretly kept in several dungeons throughout Europe until finally escaping in his mid-twenties. He could present no proof of any of this.
In 1833, Naundorff travelled to Paris where another claimant to the French throne, the Duke of Richemont, was on trial. One of the witnesses for the prosecution read out his letter as a counterclaim.
Despite the fact that Naundorff did not speak French very well, he managed to convince various former members of the Louis XVI's court that he was the Dauphin. He seemed to know everything about the private life of the royal court, gave right answers to most questions and spoke to courtiers as if he had known them as a child. One of them was Agathe de Rambaud, Louis' childhood nurse who accepted him. Others who claimed to have recognized him as the prince include Étienne de Joly, King Louis XVI's Minister of Justice, and Jean Bremond, the king's personal secretary.