The Battle of Tannenberg
The Teutonic Knights were defeated at the Battle of Tannenberg, on July 15th, 1410.
Founded in the Holy Land in 1190, the Hospitallers of Saint Mary of the Teutons in Jerusalem, or Order of Teutonic Knights, soon moved to Eastern Europe. With the support of the Holy Roman emperors and the papacy, in the 1230s they set out to conquer Prussia east of the River Vistula and to convert its pagan population to Christianity. The Knights cut Poland off from the Baltic and by 1346 they ruled the Baltic coast from the Vistula to Estonia and the Gulf of Finland, which naturally aroused intense opposition from the Poles and Lithuanians. The Poles were already Roman Catholic and in 1386 the Queen of Poland married the Grand Duke of Lithuania, who as part of the deal also became ruler of Poland and accepted Roman Catholicism for his people, removing the Knights’ main justification for their crusading activities.
In July 1410 a Polish-Lithuanian army invaded Prussia and marched towards the Order’s stronghold at Marienburg (now Malbork in Poland). The move took the Knights by surprise and the opposing armies collided near dawn in the fields near the villages of Tannenberg and Grunwald. The Knights were commanded by their Grand Master, Ulrich von Jungingen, the Poles and Lithuanians by their king and their grand duke.
Contemporary accounts of what happened are extremely sketchy, though some chroniclers stressed that the Knights were heavily outnumbered. The Polish-Lithuanian army lined up with the Polish heavy cavalry on the left and the Lithuanian light cavalry on the right. Apparently they were joined by Tatar skirmishers commanded by a former Khan of the Golden Horde and Bohemian warriors under the Hussite leader Jan Zizka. After hours of fierce fighting von Jungingen led a force of Knights he had kept in reserve in a charge against the Poles in the hope of killing the Polish king, but he was killed himself, the charge failed and the Order’s army broke. Some Knights fled to nearby woods and marshes, others retreated to the village of Grunwald, where they organised a defence of wagons tied with chains (in anticipation of the Wild West centuries later). The defence was broken and it was said that the village people had joined in the killing and more bodies were found there than anywhere else on the battlefield.
The Knights held their stronghold of Marienburg itself, but many Prussian castles surrendered to the Poles and Lithuanians. To make peace in 1411 the Order had to pay a substantial indemnity. The Polish- Lithuanian victory marked the beginning of the Teutonic Knights’ decline as a military power and the battle has been ranked ever since as one of the most important in all Polish history.