The Russo-Turkish War of 1877–1878 was a conflict between the Ottoman Empire and the Eastern Orthodox Christians coalition led by the Russian Empire and composed of Bulgaria, Romania, Serbia, and Montenegro. Fought in the Balkans and in the Caucasus, it originated in emerging 19th century Balkan nationalism. Additional factors included the Russian goals of recovering territorial losses endured during the Crimean War of 1853–56, re-establishing itself in the Black Sea and supporting the political movement attempting to free Balkan nations from the Ottoman Empire.
The Russian-led coalition won the war, pushing the Ottomans back all the way to the gates of Constantinople, leading to the intervention of the western European great powers.
As a result, Russia succeeded in claiming provinces in the Caucasus, namely Kars and Batum, and also annexed the Budjak region. The principalities of Romania, Serbia, and Montenegro, each of which had had de facto sovereignty for some years, formally proclaimed independence from the Ottoman Empire.