三帝同盟
After the formation of the German Empire in 1871, German Chancellor Otto von Bismarck wanted to portray his nation as a peacemaker and preserver of the European status quo, to gain more power for the German Empire and to unify Germany. In 1878, the Russian Empire defeated the Ottoman Empire in the Russo-Turkish War. The resulting Treaty of San Stefano gave Russia considerable influence in the Balkans, a development that outraged Austria-Hungary, Russia's chief rival in the Balkan region (despite being an ally of the Russians and the Germans in the League of the Three Emperors). Hence, in 1878, Bismarck called an international conference (the Congress of Berlin) to sort out the problem. The Treaty of Berlin that resulted from the conference reversed Russia's gains from the Treaty of San Stefano and provided the Austrians with compensation in the form of Bosnia. Despite Bismarck's attempts to play the role of an "honest broker" at the Congress of Berlin, Russo-German relations deteriorated following the conference. The Three Emperors' League was discontinued, and Germany and Austria-Hungary were free to ally against Russia.