Claim: Slovakia joined a union.

Slovakia -LRB- listen -RRB- , 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 49000 km2 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 , which itself became part of the Ottoman Empire and the Austro-Hungarian Empire . After World War I and the dissolution of the Austro-Hungarian Empire , the Slovaks and Czechs established Czechoslovakia . A separate -LRB- First -RRB- Slovak Republic -LRB- 1939 -- 1945 -RRB- existed in World War II as a client state of Nazi Germany . In 1945 , Czechoslovakia was re-established under Communist rule as a Soviet satellite . In 1989 the Velvet Revolution ended authoritarian Communist rule in Czechoslovakia . Slovakia became an independent state on 1 January 1993 after the peaceful dissolution of Czechoslovakia , sometimes known as the Velvet Divorce .   Slovakia is a high-income advanced economy with a very high Human Development Index , a very high standard of living and performs favourably in measurements of civil liberties , press freedom , internet freedom , democratic governance and peacefulness . The country maintains a combination of market economy with a comprehensive social security system . Citizens of Slovakia are provided with universal health care , free education and one of the longest paid maternity leave in the OECD . The country joined the European Union in 2004 and the Eurozone on 1 January 2009 . Slovakia is also a member of the Schengen Area , NATO , the United Nations , the OECD , the WTO , CERN , the OSCE , the Council of Europe and the Visegrád Group . The Slovak economy is one of the fastest growing economies in Europe and 3rd fastest in eurozone . Its legal tender , the Euro , is the world 's 2nd most traded currency . Although regional income inequality is high , 90 % of citizens own their homes . In 2016 , Slovak citizens had visa-free or visa-on-arrival access to 165 countries and territories , ranking the Slovak passport 11th in the world . Slovakia is the world 's largest per-capita car producer with a total of 1,040,000 cars manufactured in the country in 2016 alone and the 7th largest car producer in the European Union . The car industry represents 43 % of Slovakia 's industrial output , and a quarter of its exports .