The Knights, who were the first to organize their army for the battle, hoped to provoke Poles or Lithuanians to attack first. Because Polish army was delaying the attack the Teutonic troops, wearing heavy armor, had to stand in scorching sun for several hours waiting for an attack.
At noon the forces of Grand Duke of Lithuania Vytautas started an all-out assault on the left flank of the Teutonic forces, near the village of Tannenberg (Stebark). The Lithuanian cavalry was supported by a cavalry charge of several Polish banners on the right flank of the enemy forces. The enemy heavy cavalry counterattacked on both flanks and fierce fighting occurred.
After more than an hour, the Lithuanian light cavalry started a planned retreat maneuver
towards marshes and woods. Only three banners of Smolensk remained on the right flank after the retreat of Vytautas and his troops. One of those banners was totally destroyed.
Heavy cavalry of the Order started a disorganized pursuit after the retreating Lithuanians, which might have been a fatal mistake. The Knights entered the marshes, where Vytautas reorganized his forces to return to battle.
While the Lithuanians were retreating, heavy fighting began between Polish and Teutonic forces. Teutonic forces, commanded by Grand Komtur Kuno von Lichtenstein, concentrated on the Polish right flank. A particularly high-value target was the royal banner of Kraków. It seemed that the Knights were gaining the upper hand and at one point the royal standard-bearer Marcin of Wrocimowice lost the Kraków banner. However, it was soon recaptured and fighting continued. Jogaila deployed his reserves – the second line of his army. The arrival of fresh troops allowed the Poles to repel the enemy assault and the forces of Ulrich von Jungingen were weakened. At the same time his reserves were still busy pursuing the evading Lithuanian cavalry. When they finally returned to the battlefield, it was already too late for the Teutonic charge to succeed.
Grand Master Ulrich von Jungingen then personally led 16 banners, almost a third of the original Teutonic strength, to the right Polish flank and Jogaila deployed his last reserves, the third line of his army. Vytautas, however, also returned to the battlefield with the reorganized Lithuanian forces and joined the fierce fighting. The Teutonic forces were by then becoming outnumbered by the mass of Polish knights and the advancing Lithuanian infantry, which all of a sudden had come pouring on the battlefield from the surrounding forests.
Part of the routed units retreated to the forests while the rest retreated to the camp near the village of Grunwald, where they tried to organize the defense by using the tabor tactics: the camp was surrounded by wagons tied up with chains, serving as a mobile fortification. However, the defenses were soon broken. According to the anonymous author of the Chronicle of the Conflict of Ladislaus King of Poland with the Teutonic knights Anno Domini 1410, there were more bodies in and around the camp than on the rest of the battlefield. The pursuit after the fleeing Teutonic cavalry lasted until the dusk.
Despite the technological superiority of the Teutonic Knights, to the point of this being believed to be the first battle in this part of Europe in which field-artillery was deployed, the numbers and tactical superiority of the Polish Lithuanian alliance were to prove overwhelming.
Battle of Grunwald on Wikipedia
