Passage: Alexander was the most successful Russian reformer since Peter the Great, and was responsible for numerous reforms besides abolishing serfdom. He reorganized the judicial system, setting up elected local judges, abolishing capital punishment, promoting local self-government through the zemstvo system, imposing universal military service, ending some of the privileges of the nobility, and promoting the universities. In foreign policy, he sold Alaska to the United States in 1867, fearing the remote colony would fall into British hands if there was another war. He modernized the military command system. He sought peace, and moved away from bellicose France when Napoleon III fell. He joined with Germany and Austria in the League of the Three Emperors that stabilized the European situation. The Russian Empire expanded in Siberia and in the Caucasus and made gains at the expense of China. Faced with an uprising in Poland in 1863, he stripped that land of its separate Constitution and incorporated it directly into Russia. To counter the rise of a revolutionary and anarchistic movements, he sent thousands of dissidents into exile in Siberia and was proposing additional parliamentary reforms when he was assassinated in 1881.In the late 1870s Russia and the Ottoman Empire again clashed in the Balkans. The Russo-Turkish War was popular among the Russian people, who supported the independence of their fellow Orthodox Slavs, the Serbs and the Bulgarians. However, the war increased tension with Austria-Hungary, which also had ambitions in the region. The tsar was disappointed by the results of the Congress of Berlin in 1878, but abided by the agreement. During this period Russia expanded its empire into Central Asia, which was rich in raw materials, conquering the khanates of Kokand, Bokhara, and Khiva, as well as the Trans-Caspian region.

Question: Who were trying to gain freedom in the Russo-Turkish War?
Orthodox Slavs, the Serbs and the Bulgarians