In 1018, Bulgaria fell under the authority of the Byzantine Empire. Byzantine rule was short-lived, however. By 1185 Bulgarians had broken free of Byzantine rule and, in 1202, they established the Second Bulgarian Kingdom. Ottoman domination of the Balkan Peninsula eventually affected Bulgaria in the late 14th century, and by 1396, Bulgaria had become part of the Ottoman Empire. Following the Russo-Turkish War (1877-78) and the Treaty of Berlin (1885), Bulgaria gained some autonomy under the Ottoman Empire, but complete independence was not recognized until 1908.

During the first half of the 20 ^th century, Bulgaria was marred by social and political unrest. Bulgaria participated in the First and Second Balkan Wars (1912 and 1913) and sided with the Central Powers, and later the Axis Powers, during the two World Wars. Although allied with Germany during World War II, Bulgaria never declared war on Russia.

King Simeon II assumed control of the throne in 1943 at the age of 6 following the death of his father Boris III. Following the defeat of the Axis Powers in World War II, communism emerged as the dominant political force within Bulgaria. Simeon, who is currently Prime Minister, was forced into exile in 1946 and resided primarily in Madrid, Spain, until April 2001, when he returned to Bulgaria. By 1946 Bulgaria had become a satellite of the Soviet Union, remaining so throughout the Cold War period. Todor Zhivkov, the head of the Bulgarian Communist Party, ruled the country for much of its time under communism, and during his 27 years as leader of Bulgaria, democratic opposition was crushed, agriculture and industry were nationalized, and the Bulgarian Orthodox Church fell under the control of the state.

In 1989 Zhivkov relinquished control, and democratic change began. The first multi-party elections since World War II were held in 1990. The ruling communist party changed its name to the Bulgarian Socialist Party and won the June 1990 elections. Following a period of social unrest and passage of a new constitution, the first fully democratic parliamentary elections were held in 1991 in which the Union of Democratic Forces won. The first direct presidential elections were held the next year.

As Bulgaria emerged from the throes of communism, it experienced a period of social and economic unrest that culminated in a severe economic and financial crisis in late 1996-early 1997. With the help of the international community, former Prime Minister Ivan Kostov initiated a series of reforms in 1997 that helped stabilize the countryís economy and put Bulgaria on the Euro-Atlantic path. Elections in 2001 ushered in a new government and president. In July 2001, Bulgariaís ex-king Simeon Saxe-Coburg-Gotha became the first former monarch in post-communist Eastern Europe to become Prime Minister. The leadership in Sofia pursued Euro-Atlantic integration, democratic reform, and development of a market economy. Bulgaria officially became a member of the North Atlantic Treaty Organization on March 29, 2004 after depositing its instruments of treaty ratification in Washington, DC. Bulgaria signed its Accession Treaty with the European Union (EU) on April 25, 2005. With the support of all political parties, the Bulgarian parliament ratified the EU accession treaty on May 11, 2005, with a view towards joining the EU in 2007. Following general elections on June 25, 2005, on August 16, 2005, Sergei Stanishev of the Bulgarian Socialist Party became the new Prime Minister of a coalition government.