The last Russo-Turkish War came as a result of the anti-Ottoman uprising of 1875 in Bosnia and Herzegovina. On Russian instigation, Serbia and Montenegro joined the rebels in their war on the Ottoman Empire.  After securing Austrian neutrality in 1877, Russia went to war with the Ottoman Empire.  

The military reforms that the Russian Empire had undertaken during the previous decades played an important role in the Russian victory.  Even so, the war caught the Russians in the middle of the planned transitions.

The war was ultimately ended by the Treaty of San Stefano in 1878 and so thoroughly revised the geo-political map in favor of Russia and of Russian-influenced Bulgaria that the European powers called the Congress of Berlin to revise its terms.  After this meeting a thorough realignment of European alliances took place.