In the late 12th century German-speaking Teutonic Knights, operating from a network of castles, formed a religious-cum-military order committed to subduing the Baltic region, spreading Christianity, and protecting Christians making their pilgrimages to Jerusalem. As well as fighting the Egyptians for control of that distant holy city in the 5th and 6th Crusades (1217–1221 and 1228–1229), the Knights were also constantly fighting nearby non-Christian tribes and clans for control of their home region. From 1260 many of the Teutonic castles were besieged and captured or destroyed in ‘the Great Prussian uprising’ during which the Order suffered a series of defeats. Fighting back, in 1308 the Teutonic Order captured and sacked the strategic Polish port city of Danzig (Gdansk), committing a massacre there that sowed the seeds of a Teutonic-Polish war, which broke out in 1326 over the control of Pomerelia. In 1313 the war’s most important, though inconclusive, battle was fought at Płowce. In 1346 the Order purchased the Duchy of Estonia from Denmark, and in 1348 and 1370 it won decisive battles against the Lithuanians at the River Strėva and at Rudau. But in 1409 another (‘Great’) war broke out between the Order and a Polish-Lithuanian alliance, culminating in a major defeat for the Teutons at Tannenberg. The Christianization of the Baltics was to prove a long, uncertain and bloody business.
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