Austria–Prussia rivalry

Austria and Prussia had a long-standing conflict and rivalry for supremacy in Central Europe during the 18th and 19th centuries, termed Deutscher Dualismus (German dualism) in the German language area. While wars were a part of the rivalry, it was also a race for prestige to be seen as the legitimate political force of the German-speaking peoples. The conflict first culminated in the Seven Years' War; however, relations were not always hostile; sometimes, both countries were able to cooperate, such as during the Napoleonic Wars and the Second Schleswig War.

The Margraviate of Brandenburg was officially declared one of the seven electorates of the Holy Roman Empire by the Golden Bull of 1356. It had extended most of its territory into the eastern Neumark region, and after the War of the Jülich succession by the 1614 Treaty of Xanten also gained the Duchy of Cleves as well as the counties of Mark and Ravensberg located in northwestern Germany. It finally grew out of the Imperial borders when in 1618 the Hohenzollern electors became dukes of Prussia, then a fief of the Polish Crown, and the lands of Brandenburg-Prussia were ruled in personal union. In 1653, the "Great Elector" Frederick William acquired Farther Pomerania and reached full sovereignty in Ducal Prussia by the 1657 Treaty of Wehlau concluded with the Polish king John II Casimir Vasa. In 1701, Frederick William's son and successor Frederick I reached the consent of Emperor Leopold I to proclaim himself a King "in" Prussia at Königsberg, with respect to the fact that he still held the electoral dignity of Brandenburg and the royal title was only valid in the Prussian lands outside the Empire.

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