The Battle of Shipka Pass in August 1877.
On the night of 26–27 June, ten weeks into the campaign, the Russians crossed the Danube at Svistov. After the crossing, the Russian western column struck west along the southern bank of the river and at Plevna ran into the advance guard of the main Ottoman army of about 60,000 men. The Turkish force, which had previously defeated the Serbs, easily drove off an attack. Had they pursued the defeated Russians, they might well have advanced to the Russian bridgehead, but the Turkish commander, Osman Nuri Paça, held his ground, entrenched, and waited for the rest of his force to close up. The Russians approached again and launched another assault of 19 July, but were again driven off with heavy casualties. After a third failed assault, the Russians moved to encircle and besiege the Turks. The siege of Plevna, which came to epitomize the Russo-Turkish War, lasted until the Ottoman surrender on 10 December, following a failed Turkish breakout attempt.
The human costs of the war were high. Neither army did a good job of maintaining casualty statistics. Each army probably suffered about 150,000 military casualties. The cost to local civilians was also high, since both sides committed atrocities, and the Bulgarians resorted to what today would be termed ethnic cleansing. Estimates for the number of Bulgarian Christians killed following the April 1876 uprising vary from 15,000 to 100,000. The Christian Bulgarians responded even more harshly, killing over 250,000 Muslims, while another 500,000 refugees fled to Istanbul. A Bulgarian pogrom against Jews prompted their flight toward Istanbul, alongside the Turks. In the east, where the Armenian Christian population under Ottoman control was clearly pro-Russian, the Kurds attacked, with Ottoman encouragement, and massacred about 30,000 Armenians.
On 12 December, the Turks, beaten and running up additional debt, asked for mediation. When that brought little diplomatic action, the Ottomans appealed directly to the Russians for an armistice on 9 January 1878. On 31 January, the Russians, aware that a British fleet was on its way to the Dardanelles Straits, agreed. The Russian army was by that time camped on the approaches to Istanbul.
The Russians and Ottomans reached an agreement on 3 March 1878 at San Stefano (now Yeşilköy), a town along the front line between the Russian and Ottoman armies. Montenegro nearly doubled in size and became independent. Serbia gained territory in the south. Romania gained its independence, and Bulgaria became autonomous, though effectively independent, with its own government and army and access to the Black Sea and the Aegean. In exchange for reparations, the Russians picked up the towns of Ardahan, Kars, Batumi, and other territory along the Caucasus border with the Ottoman Empire. The Turks also agreed to allow neutral ships to pass the Straits, even in wartime.
Unfortunately, the other European powers, especially the British, who now had a fleet in the Straits, were dissatisfied with the accord. With Bismarck’s assistance, the powers convened a congress in Berlin in June. In this congress, Bulgarian autonomy was markedly weakened and its territory along the Aegean—and, along with it, the Russian position in the Balkans—reduced. Austria-Hungary gained the right to occupy and administer Bosnia and Herzegovina. In a separate agreement with the Ottomans, the British occupied Cyprus.
While the Austrians, British, and Ottomans were satisfied with the outcome in Berlin, other powers and several of the Balkan states were not, thus setting the stage for yet another round of wars. The Italians had participated in the congress, but come away with nothing. The Bulgarians were unhappy, given the weakening of their autonomous status. The Greeks were pleased to see the Bulgarian borders rolled back along the Aegean coast, but were disappointed to see the territory returned to the Ottomans. And although Bismarck did his best to play the role of honest broker, the results had clearly favored the Austrians over the Russians and spelled doom for the Dreikaiserabkommen.
Militarily, the Russo-Turkish War of 1877–1878 had not followed the patterns of the Prussian victories of the preceding decade. Operations had proceeded slowly. There were no climatic battles comparable to Königgrätz or Mars-la-Tour. The fighting at Plevna lasted for months and was marked by entrenchments akin to the final stage of the campaign in Virginia at the end of the American Civil War, but it was believed these siege conditions came about only because the Russians had failed to maneuver and foolishly attacked head on.
Since the pattern of the conflict did not fit the experiences of the German wars of unification, the consensus in Europe was to consider the Russo-Turkish War, with its mutual butchery, a non-European affair, with few, if any, lessons to be learned. As the Prussian king Frederick II sarcastically remarked, the conflict was “a war between the one-eyed and the blind.”
Both the Russian and Ottoman armies were, in fact, in the process of reform and transition, and both were far less sophisticated than the Prussian army of 1870. Observers considered both the Russian and the Turkish soldiers to be hardy and brave, but their officers to be barely competent. The siege warfare waged around Plevna was not the result of modern firepower on the battlefield, but of the poor quality of command and leadership. The Ottomans fought the war not with a general staff, but with a council located in Istanbul. The effectiveness of Turkish long-range and often unaimed rifle fire, which caused the Russians heavy and constant casualties, was considered proof of the superiority of infantry weapons over artillery and the mitrailleuse. One of the few lessons the European armies did identify and respond to was the need for infantrymen to carry their own entrenchment tools.
A French study completed in 1902 which reviewed the Russo-Turkish War noted that the conflict “occurred in an epoch when people were still too completely under the exclusive influence of the campaign of 1870 for it to be possible to study its consequences with all the desirable open-mindedness.” As a result, the European powers missed an opportunity to rethink new realities, even if the war itself did not make things perfectly clear.
The Russo-Turkish War, occurring as it did on the heels of the 1875 war scare, upset the pattern of German diplomacy. In October 1879, Bismarck concluded the Dual Alliance, a defensive treaty between Germany and Austria-Hungary aimed primarily against Russia. But the Iron Chancellor had not given up on a relationship with Russia. In June 1881, Germany, Austria-Hungary, and Russia reached a formal agreement generally termed the Three Emperors League (Dreikaiserbund). Italy, annoyed by French actions in Tunisia, joined the league in 1882.