Prussia

Prussia (; ; Old Prussian: ) was a German state centred on the North European Plain. It originated from the 1525 secularization act of the Prussian part of the State of the Teutonic Order. For centuries, the House of Hohenzollern ruled Prussia, expanding its size with the Prussian Army. Prussia, with its capital at Königsberg and then, when it became the Kingdom of Prussia in 1701, Berlin, decisively shaped the history of Germany. Prussia formed the German Empire when it united the German states in 1871. It was de facto dissolved by an emergency decree transferring powers of the Prussian government to German Chancellor Franz von Papen in 1932 and de jure by an Allied decree in 1947.

The name Prussia derives from the Old Prussians who were conquered by the Teutonic Knightsan organized Catholic medieval military order of German crusaders in the 13th century. In 1308, the Teutonic Knights conquered the region of Pomerelia with Danzig. Their monastic state was mostly Germanised through immigration from central and western Germany, and, in the south, it was Polonised by settlers from Masovia. The imposed Second Peace of Thorn (1466) split Prussia into the western Royal Prussia, a province of Poland, and the eastern Duchy of Prussia, a feudal fief of the Crown of Poland until 1657. After 1525, the Teutonic Order relocated their headquarters to Mergentheim, but managed to keep land in Livonia until 1561. The union of Brandenburg and the Duchy of Prussia in 1618 led to the proclamation of the Kingdom of Prussia in 1701.