⚔️ The Battle of Grunwald, or First Battle of Tannenberg 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, decisively defeated the German–Prussian Teutonic Knights. he battle shifted the balance of power in Central and Eastern Europe and marked the rise of the Polish–Lithuanian union as the dominant political and military force in the region.