In Bosnia and Hercegovina,this area, was settled by the Serbs and was independent by the 12th century from Rome. The area was captured by the Turks in the late 15th century. Many Bosnians accepted Islam. Bosnia and Hercegovina were placed (1878) under Austro-Hungarian government, and Austria annexed the region in 1908. The assassination (1914) of Austrian Archduke Francis Ferdinand by a Serbian nationalist in Sarajevo was one of the greatest factor of World War I. Bosnia and Hercegovina were joined to Serbia in 1918, later becoming part of Yugoslavia. During World War II they were (1941-45) part of the German state of Croatia. Slovenia and Croatia left Yugoslavia (1991), Bosnians voted (1992) for independence, and ethnic conflict broke out. Armed Serbs, many from the Yugoslav army,took control of over parts of Bosnia, and Croats seized the remainder. They established ethnic republics, and Serbs began exiling, imprisoning, and killing non-Serbs. Atrocities also occurred in Croat- and Muslim-held areas. Thousands of Bosnians were made refugees. In 1994 Bosnian Croats and Muslims agreed to a cease-fire and established, on paper, a federation that joined with Croatia in a confederation. Fighting between government and Serb forces went on into the mid-1990s and in 1995 Serbs captured two Muslim areas but lost large areas of Bosnia to Croat and Muslim forces. A truce held, and a peace treaty partitioning Bosnia into Muslim-Croat and Serb regions was signed by Bosnia, Croatia and Serbia late in 1995.