Slovakia is a landlocked country in Central Europe. It is bordered by the Czech Republic and Austria to the south, Poland to the west, Ukraine and Belarus to the north, and Germany to the east. The country has a population of about 5.5 million people. Slovakia is ranked as the 35th most populous EU member state. About 94% of Slovaks live in the urban areas of Prague, Bratislava, Košice, Nitra, Žilina and other towns and cities.Historically, Slovakia has been divided into a number of small principalities that were unified only in 1918. Prior to World War I, Slovakia consisted of a dozen principalities that were ruled by various princely houses. Since World War I, the country has been governed by a parliamentary system with a president as head of state. The capital and largest city is Bratislava. Slovakia became an official member of the United Nations in 1993.