Russo-Turkish War: The Russian Army captures Plevna after a 5-month siege. The garrison of 25,000 surviving Turks surrenders. The Russian victory is decisive for the outcome of the war and the Liberation of Bulgaria.

The Russo-Turkish War (1877–1878) was a conflict between the Ottoman Empire and a coalition led by the Russian Empire which included Romania, Serbia, and Montenegro. Precipitating factors included the Russian goals of recovering territorial losses endured during the Crimean War of 1853–1856, re-establishing itself in the Black Sea and supporting the political movement attempting to free Balkan nations from the Ottoman Empire. The Romanian army had around 114,000 soldiers in the war. In Romania the war is called the Russo-Romanian-Turkish War (1877–1878) or the Romanian War of Independence (1877–1878).

The siege of Plevna or Pleven, was a major battle of the Russo-Turkish War of 1877–1878, fought by the joint army of the Russian Empire and the Kingdom of Romania against the Ottoman Empire. After the Russian army crossed the Danube at Svishtov, it began advancing towards the centre of modern Bulgaria, with the aim of crossing the Balkan Mountains to Constantinople, avoiding the fortified Turkish fortresses on the Black Sea coast. The Ottoman army led by Osman Pasha, returning from Serbia after a conflict with that country, was massed in the fortified city of Pleven, a city surrounded by numerous redoubts, located at an important road intersection.

The Ottoman Empire, also called the Turkish Empire, was an imperial realm that controlled much of Southeast Europe, West Asia, and North Africa from the 14th to early 20th centuries; it also controlled parts of southeastern Central Europe, between the early 16th and early 18th centuries.

The Liberation of Bulgaria is the historical process as a result of the Bulgarian Revival. In Bulgarian historiography, the liberation of Bulgaria refers to those events of the Tenth Russo-Turkish War (1877–1878) that led to the re-establishment of the Bulgarian state under the Treaty of San Stefano of 3 March 1878.