Claim: Hungary's number two city by size is Debrecen.

Hungary -LRB- -LSB- ˈhʌŋɡəri -RSB- Magyarország -LSB- ˈmɒɟɒrorsaːɡ -RSB- -RRB- is a unitary parliamentary republic in Central Europe . It covers an area of 93,030 km2 , situated in the Carpathian Basin , and is bordered by Slovakia to the north , Romania to the east , Serbia to the south , Croatia to the southwest , Slovenia to the west , Austria to the northwest , and Ukraine to the northeast . With about 10 million inhabitants , Hungary is a medium-sized member state of the European Union . The official language is Hungarian , which is the most widely spoken non-Indo-European language in Europe . Hungary 's capital and largest metropolis is Budapest , a significant economic hub , classified as a global city . Major urban areas include Debrecen , Szeged , Miskolc , Pécs and Győr .   Following centuries of successive habitation by Celts , Romans , Slavs , Gepids and Avars , the foundation of Hungary was laid in the late 9th century by the Hungarian grand prince Árpád in the conquest of the Carpathian Basin . His great-grandson Stephen I ascended to the throne in 1000 , converting the country to a Christian kingdom . By the 12th century , Hungary became a middle power within the Western world , reaching a golden age by the 15th century . Following the Battle of Mohács in 1526 and about 150 years of partial Ottoman occupation -LRB- 1541 -- 1699 -RRB- , Hungary came under Habsburg rule , and later formed the great power Austro -- Hungarian Empire together with Austria .   Hungary 's current borders were established in 1920 by the Treaty of Trianon after World War I , when the country lost 71 % of its territory , 58 % of its population , and 32 % of ethnic Hungarians . Following the interwar period , Hungary joined the Axis Powers in World War II , suffering significant damage and casualties . Hungary became a satellite state of the Soviet Union , which contributed to the establishment of a four-decade-long communist dictatorship -LRB- 1947 -- 1989 -RRB- . The country gained widespread international attention regarding the Revolution of 1956 and the seminal opening of its previously-restricted border with Austria in 1989 , which accelerated the collapse of the Eastern Bloc . On 23 October 1989 , Hungary again became a democratic parliamentary republic .   In the 21st century , Hungary is a middle power and has the world 's 57th largest economy by nominal GDP , as well as the 58th largest by PPP , out of 188 countries measured by the IMF . As a substantial actor in several industrial and technological sectors , it is both the world 's 36th largest exporter and importer of goods . Hungary is a high-income economy with a very high standard of living . It keeps up a social security and universal health care system , and a tuition-free university education . Hungary performs well in international rankings : it is 20th in quality of life , 25th in inequality-adjusted human development , 32nd in the Social Progress Index , and ranks as the 19th safest country in the world .   Hungary joined the European Union in 2004 and has been part of the Schengen Area since 2007 . Hungary is a member of the United Nations , NATO , WTO , World Bank , the AIIB , the Council of Europe and Visegrád Group . Well known for its rich cultural history , Hungary has contributed significantly to arts , music , literature , sports and science and technology . Hungary is the 11th most popular country as a tourist destination in Europe , attracting 14.3 million international tourists in 2015 . It is home to the largest thermal water cave system , the second largest thermal lake in the world , the largest lake in Central Europe , and the largest natural grasslands in Europe .