Long a crossroads of civilizations (archaeological finds date back to 4600 B.C.), Bulgaria was first recognized as an independent state in AD 681. Bulgarian Orthodox Christanity, which became a hallmark of national identity, was established in the 9th century. Bulgaria was ruled by the Byzantine Empire from 1018 to 1185 and the Ottoman Empire from 1396 to 1878. In 1879, Bulgaria adopted a democratic constitution and invited a German nobleman, Alexander of Battenburg, to be prince.
In the early part of the 20th century, in an effort to gain Macedonian and other territories, Bulgaria engaged in two Balkan wars and become allied with Germany during World War I. It suffered disastrous losses as a result. The interwar period was dominated by economic and political instability and by terrorism as political factions, including monarchists and communists, struggled for influence. In World War II, Bulgaria ultimately allied again with Germany but protected its Jewish population of some 50,000 from the Holocaust. When King Boris III died in 1943, political uncertainty heightened. The Fatherland Front, an umbrella coalition led by the Communist Party, was established. This coalition backed neutrality and withdrawal from occupied territories. Bulgaria tried to avoid open conflict with the Soviet Union during the war, but the U.S.S.R. invaded in 1944 and placed the Fatherland Front in control of government.
After Bulgaria's surrender to the Allies, the Communist Party purged opposition figures in the Fatherland Front, exiled young King Simeon II, and rigged elections to consolidate power. In 1946, a referendum was passed overwhelmingly, ending the monarchy and declaring Bulgaria a people's republic. In a questionable election the next year, the Fatherland Front won 70% of the vote and Communist Party leader Georgi Dimitrov became Prime Minister. In 1947, the Allied military left Bulgaria, and the government declared the country a communist state. Forty-two years of heavy-handed totalitarian rule followed. All democratic opposition was crushed, agriculture and industry were nationalized, and Bulgaria became the closest of the Soviet Union's allies. Unlike other countries of the Warsaw Pact, however, Bulgaria did not have Soviet troops stationed on its territory.
Dimitrov died in 1949. Todor Zhivkov became Communist Party Chief in 1956 and Prime Minister in 1962. Zhivkov held power until November 1989, when he was deposed by members of his own party, soon renamed the Bulgarian Socialist Party (BSP).
Bulgaria has been a parliamentary democracy since 1990. Four parliamentary and two presidential elections have been held since the fall of the communist dictatorship in November 1989, each followed by peaceful and orderly change.