League of the Three Emperors
The League of the Three Emperors or Union of the Three Emperors (German: Dreikaiserbund) was an alliance between the German, Russian and Austro-Hungarian Empires, from 1873 to 1887. Chancellor Otto von Bismarck took full charge of German foreign policy from 1870 to his dismissal in 1890.
Source: Wikipedia — League of the Three Emperors (CC BY-SA 4.0)