The stories about Münchhausen were first collected and published by an anonymous author in 1781. An English version was published in London in 1785, by Rudolf Erich Raspe, as Baron Munchhausen's Narrative of his Marvellous Travels and Campaigns in Russia, also called The Surprising Adventures of Baron Munchhausen. It is not clear how much of the story material derives from the Baron himself; however, it is known that the majority of the stories are based on folktales that have been in circulation for many centuries before Münchhausen's birth. (Summary by Wikipedia)