Slovakia, officially the Slovak Republic, is a landlocked country in central Europe. It is bordered by the Czech Republic and Austria to the west, Poland to the north, Ukraine to the east and Hungary to the south. Slovakia's territory spans about 49,000 square kilometres and is mostly mountainous. The population is over 5 million and comprises mostly ethnic Slovaks. The capital and largest city is Bratislava. The official language is Slovak.
The Slavs arrived in the territory of present-day Slovakia in the 5th and 6th centuries. In the 7th century, they played a significant role in the creation of Samo's Empire and in the 9th century established the Principality of Nitra. In the 10th century, the territory was integrated into the Kingdom of Hungary. After World War I and the dissolution of the Austro-Hungarian Empire, the Slovaks and Czechs established Czechoslovakia. A separate Slovak Republic existed in World War II as a client state of Nazi Germany. In 1945, Czechoslovakia was re-established and under Communist rule became a Soviet satellite. In 1989, the Velvet Revolution ended Communist rule in Czechoslovakia.