The Treaty of Berlin was the final act of the Congress of Berlin (13 June – 13 July 1878), by which the United Kingdom, Austria-Hungary, France, Germany, Italy, Russia and the Ottoman Empire under Sultan Abdul Hamid II revised the Treaty of San Stefano signed on 3 March the same year. The most important task of the Congress was to decide the fate of the Principality of Bulgaria established in the Treaty of San Stefano, even though Bulgaria itself was excluded from participation in the talks at Russian insistence. At the time, being non-existent on the world map, Bulgaria was not a subject of international law, neither were the Bulgarians themselves. This exclusion was already an established fact in the Constantinople Conference of the Great Powers, held one year before without any Bulgarian participation. The most notable result of the conference is the de jure recognition of de facto independent states of Romania, Serbia and Montenegro.