The battle took place on the central Poland on July 1410, was one of largest battles ever fought in medieval Europe. It involved over 50000 combatants, many of them were knights. One side there were great Teutonic Knights supported by the knights from Kulm, Konigsberg, and Brandenburg. The other side consisted of armies of Poland and Lithuania. The battle was very violent and ended with destruction of one side and helped to determine the borders of Eastern Europe for many centauries to come.
Teutonic Knights were trained members of new monastic orders that were formed during the Crusades. As the name implies they were mainly Germanic, and they eventually focused their attention almost entirely on Northern and Eastern Europe. The Knights set up a network of massive castles from which they launched their raids, and they aggressively pursued their chosen enemies, steadily expanding their territory and driving east. This expansion brought them to conflict with Poland. At this time the leader of the Teutonic knight was a German nobleman named Ulrich von Jungingen. Over the years, he served in nearly every major position in the Teutonic Knights’ hierarchy.
At this time the ruler of the Poland was a princess named Jadwiga. She was crowned at age 10 and could speak lots of languages and had a good education. Meanwhile the ruler of the Lithuania was a young duke name Jagiello. Jagiello had been raised a pagan, but he converted to Orthodox Christianity. Because he now wanted to marry Jadwiga, he agreed to become Roman Catholic. In 1386, the two married, and the countries of Poland and Lithuania were united. But Jagiello faced threats to his control of Lithuania, foremost fromhis cousin Vytautas, who had persuaded the Teutonic Knights to
undertake several military actions against Lithuania, given that they refused to recognize Jagiello as a genuine Christian monarch. After several years, Jagiello and Vytautas agreed to shelve their
differences and their rivalry and, instead, work together for the benefit of Lithuania. In practical terms, Jagiello was the nominal ruler of Lithuania, but Vytautas oversaw day-to-day affairs. In 1399, Queen Jadwiga died, leaving Jagiello the king of Poland in both name and reality.
The situation was volatile, and the spark that ignited it into open warfare was a rebellion against the Teutonic Knights by the inhabitants of a region called Samogitia in western Lithuania. With Ulrich taking a hard line in negotiations, Jagiello and Vytautas determined to launch an invasion of the Knights’ territory.
Lithuania hoped to recover Samogitia and Poland to acquire a lost province of its own, Pomerania. To achieve these aims, Jagiello and Vytautas decided to launch a strike northwards towards the Knights’ main stronghold at Marienbad. As the allied army marched north, the Knights’ army shadowed their movements, and eventually, the two forces drew together between the villages of Tannenberg and Grunwald. Most modern analysts believe that the army of the Teutonic Knights had 25,000 to 30,000 men, and the allied army of the Poles and Lithuanians, about 40,000 to 55,000.
On July 15, 1410, the two armies faced off across a shallow valley. The elite of the Teutonic Knights were deployed on the left side of the line, while the guest Crusaders constituted the right wing. On the other side, the Lithuanians formed the allied army’s right wing, facing the Knights, while the Poles were deployed on the left.
The combined Polish–Lithuanian army swept forward along the line, and the two sides crashed in a head of conflict. This phase of intense hand-to-hand combat continued for nearly an hour, with neither side giving way. Then, abruptly, the Lithuanians and some of the allied forces on the right wing pulled back and apparently went into full retreat
Despite the collapse of the right, the Poles held firm in the center and on the left battling the Teutonic knights. Some of the Poles now even drove in to the gap created by the advance created by the advance of the guest Crusaders and turned to threaten the exposed flank of the knights.
At this crucial stage of the battle, Ulrich mounted his horse, gathered the reserve force of the Knights around him, and led a thundering charge in a wedge formation diagonally across the field and directly at the polish royal eagle banner, under which he assumed he would find Jagiello.
Had they broken through the Polish ranks and killed Jagiello, this charge might well have won the battle, but Vytautas saw it coming and, collecting a force of his best-equipped knights, moved to intercept. A fire battle ensured but the charge lost its momentum and faltered just short of Jagiello.
The battle now turned decisively against the Germans. The remaining Knights were assaulted from the rear by Polish light cavalry, while on the right, the Lithuanians swept back onto the fields, trapping the returning guest Crusaders between the and the victorious Poles.
By the end of the day, between 10,000 and 15,000 on the German side were dead, with about the same number captured. It was a crushing defeat; the full-ranking Teutonic Knights were almost wiped out, with more than 200 lying dead on the battle field, along with the entire leadership of the order.