Between 1875 and 1877 anti-Ottoman revolts took place in several Balkan countries, most notably Bulgaria, where the April Uprisings of 1876 were brutally suppressed by irregular bashi-bazouks. The international outrage at the Bulgarian massacre – particularly on the part of Russia, who saw itself as a protector of Orthodox Christians in general and Bulgarians in particular – triggered several diplomatic efforts over the next year. After the failure of these diplomatic attempts, Russia declared war on the Ottoman Empire on 24 April 1877, launching the Russo-Turkish War, which is known in Romanian historiography as the War of Independence.