Following the heavy defeat of the Teutonic Order of Knights by the Polish-Lithuanian alliance at Tannenberg in 1410, the Order’s control and reputation began to weaken. Most of the Order’s senior knights had been killed on the battlefield, and the remainder were obliged to fall back and defend their capital at Marienburg. However, under the First Peace Treaty of Thorn (1411), they still retained most of their territories. But with internecine feuds, further decline set in. In the Gollub War (1422), the Order lost Samogitia and some border regions to the Duchy of Lithuania. They also fought with knights from other German city states in the Rhineland and against the Hussites to the south. In 1431 the Order was defeated by the Poles at the battle of Dabki, and defeats by a Prussian-Polish alliance in the ‘Thirteen Years’ War’ (1454–1466) further reduced the territories controlled by the Teutons, who were obliged under the Second Treaty of Thorn (1466) to move their capital to Königsberg and to relinquish control of all but eastern Prussia and parts of Livonia. In a further Polish–Teutonic War (1519–1521), the Order was later ousted from Prussia altogether, and their power was eventually reduced to a series of isolated ‘commanderies’ or ‘bailiwicks’ scattered across Europe.
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