Preußen - Österreich
Prussia - Austria: The relations between Austria and Brandenburg-Prussia, which had risen to an important power within the Empire, became closer at the end of the 17th century. With the approval by Leopold I, Elector Friedrich III assumed, on January 18, 1701, the title of "King in Prussia" for the Duchy of Prussia outside the bounds of the Holy Roman Empire. After the conquest of the Austrian province of Silesia by King Friedrich II (1740), the relations between Austria and Prussia were marked by several wars (Austrian Succession, War of the 1740-1748, Seven Years´ War 1756-1763, Bavarian Succession, War of the 1778/79) and a hostile rivalry between the two states. The Reichenbach Convention of July 27, 1790 ended the conflicts. Austria and Prussia concluded an alliance against France at Pillnitz on August 27, 1791; however, this alliance proved a failure during the First Coalition War and Prussia left it in 1795 (Napoleonic Wars). It was only in 1813 that another alliance against France was formed between the two states, which eventually led to the overthrow of Napoleon. At the 1815 Congress of Vienna the rivalry between Austria and Prussia, which lasted throughout the existence of the German Confederation, broke out again. After the 1863/1864 German-Danish War, in which they cooperated again, the decisive Austro-Prussian War followed in1866, which led to the dissolution of the German Confederation after the Austrian defeat near Königgrätz and enabled Prussia to establish the Deutsches Reich. After this was proclaimed in 1871, the monarchs resumed friendly relations (meeting in Gastein in August 1871 and March 1879), and on October 7, 1879, they formed an alliance which made them brothers in arms during the First World War. The political conflicts were accompanied by scholarly disputes, especially among historiographers, where the kleindeutsch (Small German) Prussian (H. Sybel, H. v. Treitschke) and the großdeutsch (Large German) Austrian Schools (J. v. Ficker) competed with each other.
After the establishment of railways and the increase of industrial activities the two countries maintained strong economic ties which, however, were not restricted to Prussia and extended all over Germany.
The relations Germany-Austria developed under different conditions in the 20th century. After the end of World War II the German Democratic Republic became the geographic successor state of Prussia until Germany´s reunification in 1990.
Literature: A. Kohler, Das Reich im Spannungsfeld des preußisch-österreichischen Gegensatzes, in: Wiener Beiträge zur Geschichte der Neuzeit 2, 1975.