The Principality of Serbia was an autonomous, later sovereign state in the Balkans that came into existence as a result of the Serbian Revolution. Its creation was negotiated first through an unwritten agreement between Miloš Obrenović, leader of the Second Serbian Uprising, and Ottoman official Marashli Pasha, followed by a series of decrees of the Sublime Porte in 1828–1833. Its de facto independence ensued in 1867, following the evacuation of the remaining Ottoman troops from the Belgrade Fortress and the country; its independence was recognized internationally in 1878 by the Treaty of Berlin. In 1882 the country was elevated to the status of kingdom.