Teutonic Knights or Teutonic Order (tōōtŏn´Ĭk), German military religious order founded (1190–91) during the siege of Acre in the Third Crusade. It was originally known as the Order of the Knights of the Hospital of St. Mary of the Teutons in Jerusalem. The order was one of nobles, and the knights took the monastic vows of poverty, chastity, and obedience. Under Hermann von Salza, its grand master in the early 13th cent., the order moved to E Europe and rose to prominence. After a brief period (1221–25) in Transylvania, where it fought for King Andrew II of Hungary against the Cumans, the order responded to a call (1226) of the Polish Duke Conrad of Mazovia for a crusade against the Prussians. Holy Roman Emperor Frederick II granted (1226) it vast privileges, and Conrad invested it with conquered lands. However, Hermann von Salza placed (1234) his conquests under papal suzerainty and set about to organize them as a separate German state. The Poles were long unsuccessful in asserting their claim to suzerainty over the order. After some 50 years of successful campaigning the knights had subdued Prussia (i.e., the lands later known as East Prussia and West Prussia) and founded numerous towns and fortresses. The expansion of the Livonian Brothers of the Sword took place further east; they were united with the Teutonic Order from 1237 to 1525. The Prussians, who had repeatedly risen in revolt, were reduced to serfdom (13th cent.), and German emigrants arrived to settle the land. The order was strongly centralized, and its administration and colonization laid the foundation of the Prussian state. The knights administered their lands from Marienburg, but they granted considerable freedom to the cities, many of which joined the Hanseatic League. In 1263 the pope allowed the knights to monopolize the grain trade. Their seizure (1308–9) of Pomerelia (see Pomerania) from Brandenburg brought on intermittent warfare with Poland, which claimed the province. In 1410 the Poles and Lithuanians routed the order at Tannenberg; successive warfare with Poles ensued and by the second Treaty of Torun (1466) the knights were forced to cede West Prussia and Pomerelia to Poland, retaining only East Prussia as a Polish fief. Their capital was transferred to Königsberg in East Prussia. The fatal blow to the order was delivered in 1525 by its own grand master, Albert of Brandenburg, who accepted the Reformation, declared Prussia a secular duchy, and was invested as duke by Sigismund I of Poland. Stripped of all importance, the Teutonic Order continued in Catholic Germany until its remaining possessions were secularized in 1809. It was later revived in Austria, but as an honorary body. The habit of the order was a white robe with a black cross.