Bulgaria is a country in Southeastern Europe. It borders five countries: Romania to the north mostly along the Danube, Serbia and the Republic of Macedonia to the west, and Greece and Turkey to the south, as well as the Black Sea, which comprises its entire eastern border.

Situated in a region once inhabited by the ancient Thracians and later by Greeks and Romans, Bulgaria is a successor of a powerful European medieval empire which at times covered most of the Balkans and spread its culture and literature among the Slavic peoples. After almost five centuries of Ottoman rule, Bulgaria was reestablished as a constitutional monarchy in 1878. Part of the Eastern Bloc after World War II, today Bulgaria is a democratic, unitary, constitutional republic, a member of the European Union and NATO.

Geographically and climatically, Bulgaria is noted for its diversity, with the landscape ranging from the Alpine snow-capped peaks in Rila, Pirin and the Balkan Mountains to the mild and sunny weather of the Black Sea coast, from the typically continental Danubian Plain (ancient Moesia) in the north to the strong Mediterranean influence in the valleys of Macedonia and the lowlands in the southernmost parts of Thrace. Bulgaria comprises portions of the classical regions of Thrace, Moesia, and Macedonia. The southwest of the country is mountainous with two alpine ranges - Rila and Pirin and further east are the lower but more extensive Rhodope Mountains. Rila mountain includes the highest peak of the Balkan Peninsula, peak Musala at 2,925 meters (9,596 ft); the long range of the Balkan mountains runs west-east through the middle of the country, north of the famous Rose Valley. Hilly country and plains are found in the southeast, along the Black Sea coast in the east, and along Bulgaria's main river, the Danube in the north. Other major rivers include the Struma and the Maritsa river in the south. There are around 260 glacial lakes situated in Rila and Pirin, several large lakes on the Black Sea coast and more than 2,200 dam lakes. Mineral springs are in great abundance located mainly in the south-western and central parts of the country along the faults between the mountains.

The Bulgarian climate is temperate, with cold, damp winters and hot, dry summers, and Mediterranean along the Black Sea coast. The barrier effect of the Balkan Mountains is felt throughout the country: Northern Bulgaria is slightly cooler and receives more rain than the southern regions. Average precipitation in Bulgaria is about 630 millimetres per year. The driest areas are Dobrudzha and the northern coastal strip, while the higher parts of the mountains Rila and Stara Planina receive the highest levels of precipitation.

Bulgaria joined NATO on March 29, 2004 and signed the Treaty of Accession on 25 April 2005. It became a full member of the European Union on 1 January 2007. The country has been a member of the United Nations since 1955, and is a founding member of OSCE. As a Consultative Party to the Antarctic Treaty, Bulgaria takes part in the governing of the territories situated south of 60° south latitude.

Bulgaria's economy contracted dramatically after 1989 with the loss of the market of the Council for Mutual Economic Assistance (COMECON) member states, to which the Bulgarian economy had been closely tied. The standard of living fell by about 40%, but it regained pre-1990 levels in June 2004. United Nations sanctions against Yugoslavia and Iraq took a heavy toll on the Bulgarian economy. The first signs of recovery emerged in 1994 when the GDP grew and inflation fell. During the government of Zhan Videnov's cabinet in 1996, the economy collapsed due to lack of international economic support and an unstable banking system. Since 1997, the country has been on the path to recovery, with GDP growing at a 4% – 5% rate, increasing FDI, macroeconomic stability and European Union membership.