One of the first Serbian states, Raška, was founded in the first half of the 7th century on Byzantine territory by the Unknown Archont, the founder of the House of Vlastimirović; it evolved into the Serbian Empire under the House of Nemanjić. In the modern era Serbia has been an autonomous principality (1817–1878), an independent principality and kingdom as the Kingdom of Serbia (1878–1918), part of the Kingdom of the Serbs, Croats and Slovenes (1918–1941) (renamed the Kingdom of Yugoslavia in 1929), a Nazi-occupied puppet state (1941–1944), a socialist republic within the Socialist Federal Republic of Yugoslavia (1945–1992), a republic within the Federal Republic of Yugoslavia (1992–2003), and a republic within the State Union of Serbia and Montenegro (2003–2006), before proclaiming independence as the Republic of Serbia on June 5, 2006.