Romania is a country located at the intersection of Central and Southeastern Europe, on the lower Danube, within and outside the Carpathian arch, bordering on the Black Sea. Romania shares a border with Hungary and Serbia to the west, Ukraine and Moldova to the northeast and east, and Bulgaria to the south.
At 238,400 square kilometers (92,000 sq mi), Romania is the ninth largest country of the European Union by area, and has the seventh largest population of the European Union with over 19 million people. Its capital and largest city is Bucharest, the tenth largest city in the EU, with a population of around two million.
The United Principalities emerged when the principalities of Moldavia and Wallachia were united under Prince Alexander Ioan Cuza in 1859. In 1881, Carol I of Romania was crowned, forming the Kingdom of Romania. Independence from the Ottoman Empire was declared on 9 May 1877, and was internationally recognized the following year. At the end of World War I, Transylvania, Bukovina and Bessarabia united with the Kingdom of Romania. Greater Romania emerged into an era of progression and prosperity that would continue until the eve of World War II. That war caused the rise of a military dictatorship in Romania, leading it to fight on the side of the Axis powers from 1941 to 1944. It then switched sides in 1944 and joined the Allies. By the end of the war, many north-eastern areas of Romania's territories were occupied by the Soviet Union, and Romania forcibly became a socialist republic and a member of the Warsaw Pact.
With the fall of the Iron Curtain and the 1989 Revolution, Romania began its transition towards democracy and a capitalist market economy. After a decade of post-revolution economic problems and living standards decline, extensive reforms fostered economic recovery. As of 2010, Romania is an upper middle-income country with high human development.
Romania joined NATO on 29 March 2004, the European Union on 1