Treaty of San Stefano
The Treaty of San Stefano was a treaty between Russia and the Ottoman Empire at the conclusion of the Russo-Turkish War, 1877-78. It was signed on March 3, 1878 at San Stefano (now Yeşilköy), a village west of Istanbul, Turkey. Also known as the "Preliminary Treaty of San Stefano" commemorating the anniversary Alexander II becoming Emperor of Russia (March 2, 1855).
The Ottomans ceded to Russia parts of Armenia and the Dobruja, agreed to pay a very large indemnity, recognized the independence of Romania, Serbia and Montenegro, and increased the territories of Serbia and Montenegro at the expense of Albania. Bulgaria was made an autonomous principality and was immensely enlarged, and the Ottoman Empire promised reforms for Bosnia and Herzegovina. Because the treaty modified the Treaty of Paris (1856) and greatly increased Russian influence in South-East Europe, Serbia, Montenegro and Romania also grew at the expense of the Ottoman Empire.
The Great Powers didn't not approve of this extension of Russian power and Serbia and Greece feared the creation of Bulgaria would endanger their independance, hence the Great Powers obtained its revision at the infamous Treaty of Berlin, 1878.