三帝同盟
The first League of the Three Emperors was in effect from 1873 to 1878. A second one was established June 18, 1881, and lasted for three years. It was renewed in 1884 but lapsed in 1887. Both alliances ended because of continued strong conflicts of interest between Austria-Hungary and Russia in the Balkans. The second treaty provided that no territorial changes should take place in the Balkans without prior agreement and that Austria could annex Bosnia and Herzegovina when it wished; in the event of war between one party and a great power not party to the treaty, the other two parties were to maintain friendly neutrality.