The mystery of Kaspar Hauser and whether he was the hereditary Prince of Baden is considered to be one of the greatest historical mysteries of the 19th century. Previous genetic research trying to answer the question gave conflicting results. Professor Turi King discusses her work and the work carried out by the team, led by Walther Parson, which brought new genetic techniques to bear on the question and which shows that Kaspar Hauser was not the hereditary Prince of Baden.