 Complete the following phrase:  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 