Montenegro won independence from Serbia when Serbia was conquered by the Turks in 1389. It was ruled by prince-bishops, 1516-1852. It became a kingdom in 1910 but joined Serbia and other areas in 1918 to form Yugoslavia (then called the Kingdom of the Serbs, Croats, and Slovenes). It was made a Communist republic in 1945. During 1991-92 the Yugoslav federation, which was made up of six republics, collapsed and Montenegro and Serbia formed a new Yugoslav federation.
Milan Djukanovic, who was appointed Prime Minister in 1991 and elected President in 1997, sought increased autonomy for the province. During NATO's war against Yugoslavia in 1999, Djukanovic refused the federal government's demand to declare war on NATO countries. After the war, Montenegro presented Yugoslav authorities with a series of demands for greater autonomy. Negotiations resulted in the new country of Serbia and Montenegro in 2003, a looser union replacing the former Yugoslav federation of 1992.
Many people in Montenegro continued to call for independence from Serbia. Montenegro's legislative assembly ordered a referendum on independence, which was held in 2006. In the referendum, a majority of the voters approved independence. Shortly afterward, Montenegro declared its independence. Serbia then declared its own independence.