a republic in SE Europe, on the Balkan Peninsula on the Black Sea: under Turkish rule from 1395 until 1878; became an independent kingdom in 1908 and a republic in 1946; joined the EU in 2007; consists chiefly of the Danube valley in the north and the Balkan Mountains in the central part, separated from the Rhodope Mountains of the south by the valleyof the Maritsa River. Language: Bulgarian. Religion: Christian (Bulgarian Orthodox) majority. Currency: lev. Capital: Sofia. Pop: 7 084 571 (2017 est). Area: 110 911 sq km (42 823 sq miles)