The trial of Peter von Hagenbach by an "ad hoc" tribunal of the Holy Roman Empire in 1474, was the first "international" recognition of commanders' obligations to act lawfully. Hagenbach was put on trial for atrocities committed during the occupation of Breisach, found guilty of war crimes and beheaded. Since he was convicted for crimes "he as a knight was deemed to have a duty to prevent", Hagenbach defended himself by arguing that he was only following orders from the Duke of Burgundy, Charles the Bold, to whom the Holy Roman Empire had given Breisach. Despite the fact no explicit use of a doctrine of "command responsibility" existed, it is seen as the first trial based on this principle.