"East Prussia" is sometimes used to refer to the Duchy of Prussia (1525-1618) East Prussia ( ; or Rytprūsiai; ; or Vostochnaya Prussiya) refers to the main part of the region of Prussia along the southeastern Baltic Coast from the 13th century to 1945. From 1772-1829 and 1878-1945, the Province of East Prussia was a province of the German state of Prussia.East Prussia enclosed the bulk of the ancestral lands of the Baltic Old Prussians, whose language became extinct by the 18th century. During the 13th century, the native Prussians were conquered by the crusading Teutonic Knights. The indigenous Balts who survived the conquest were gradually converted to Christianity. Because of Germanization and colonization over the following centuries, Germans became the dominant ethnic group, while Poles and Prussian Lithuanians formed minorities.
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