Day of the Battle of Jalgiris
Description:
Polish King Vladislav II Jagiello, who previously ruled in Vilna and called Jagiello, and Lithuanian Grand Duke Vytautas defeated the Germans. The success of Jagaila and Vytautas is usually called the triumph of Slavic weapons, but many thousands of Tatar cavalry fought in the Polish-Lithuanian army. The army of the Grand Duke of Lithuania, however, consisted mainly of Slavs from the territory of present-day Belarus and the Smolensk lands. At first, military luck turned away from future winners: failing to break through the defense of the knights, the Tatar cavalry fled in fear.
However, the efforts of the Slavic troops, including the Smolensk regiments, managed to intercept the initiative, and the Crusaders suffered one of the most severe defeats in history. But it was not possible to finish off the Teutons at that time: the army of Jagiila and Vytautas belatedly began the siege of Marienburg, the order's capital, and the knights managed to strengthen the city.
But the Germans could no longer compete with their powerful neighbors, Poland and Lithuania, and in 1466 the Teutonic Order successfully ceased to exist.