Bulgaria, situated in the eastern Balkans, has been undergoing a slow and painful transition to a market economy since the end of Communist rule.
A predominantly Slavonic-speaking, Orthodox Christian country, Bulgaria was the birthplace of the Cyrillic alphabet, which was created there towards the end of the 9th century AD.
It was long influenced by Byzantine culture then was part of the Ottoman Empire for 500 years before gaining its independence in the 19th century.
After the Second World War it became a satellite of the Soviet Union, but is now a member country of the EU and NATO.
President: Rumen Radev
Rumen Radev became Bulgaria's fifth democratically elected president when he was sworn in for a five-year term in January 2017.
A former air force commander, Mr Radev is a relative newcomer to politics who ran as an independent candidate with the backing of the opposition Socialists.
His victory in the presidential election led to the resignation of Prime Minister Boyko Borisov and early parliamentary elections.
Mr Radev has pledged to maintain Bulgaria's position as a member of the European Union and NATO while also improving historically important ties with Russia.
In his inauguration speech, Mr Radev highlighted the need for continuity and pledged to work for a "united society in the name of democracy".
Prime minister: Boyko Borisov
Boyko Borisov became prime minister for the third time in May 2017 following the victory of his GERB party in the April snap parliamentary election.
Mr Borisov, who is the founder of GERB, first became prime minister in July 2009. Mr Borisov's GERB party has formed a coalition with the United Patriots - an anti-immigrant grouping.
He is a former bodyguard who rose through the ranks in the Sofia police department and in the interior ministry. He was mayor of Sofia from 2005 to 2009.
Global media giants have a stake in Bulgaria's lively broadcasting market. TV is the most popular medium.
International media group CME runs bTV, Bulgaria's most-watched channel. Scandinavian company MTG operates national station Nova TV.
There are several private regional TVs and many private radio stations. Cable and satellite are the main distribution platforms. Media ownership is concentrated among a handful of individuals.
Some key dates in Bulgaria's history:
1018-1185 - Bulgaria is part of Byzantine empire.
1396 - Ottoman Empire completes conquest of Bulgaria. Next five centuries are known as era of the "Turkish yoke".
1876 - Nationwide uprising against Ottoman rule is violently suppressed.
1878 - Treaty of San Stefano - signed by Russia and Turkey at the end of their war of 1877-78 - recognises an autonomous Bulgaria.
1908 - Bulgaria declares itself an independent kingdom. Ferdinand of Saxe-Coburg-Gotha assumes title of tsar.
1914-18 - First World War. Bulgaria allies itself with Germany. Some 100,000 Bulgarian troops are killed, the most severe per capita losses of any country involved in the war.
1939-45 Second World War - Soviet army invades German-occupied Bulgaria in 1944. Soviet-backed Fatherland Front takes power.
1947 - New constitution along Soviet lines establishes one-party state.
1954 - Todor Zhivkov becomes Communist Party general secretary. Bulgaria becomes staunch USSR ally.
1971 - Zhivkov becomes president.
1989 - Reforms in the Soviet Union inspire demands for democratisation. Zhivkov ousted.
1991 New constitution proclaims Bulgaria a parliamentary republic and provides broad range of freedoms.