The Battle of Grunwald, First Battle of Tannenberg or Battle of Žalgiris, was fought on 15 July 1410 during the Polish–Lithuanian–Teutonic War. The alliance of the Kingdom of Poland and the Grand Duchy of Lithuania, led respectively by King Władysław II Jagiełło (Jogaila) and Grand Duke Vytautas (Witold; Vitaŭt), decisively defeated the German–Prussian Teutonic Knights, led by Grand Master Ulrich von Jungingen. Most of the Teutonic Knights' leadership were killed or taken prisoner.