Hungary is a Central European republic. It is bordered on the north by Slovakia, the northeast by Ukraine, the east and southeast by Romania, the south by Serbia, the southwest by Croatia and Slovenia, and the west by Austria. Hungary is a country in the Carpathian Basin that spans 93,030 square kilometers and has a population of ten million people. The official language, Hungarian, is the world's most widely spoken Uralic language and one of Europe's few non-Indo-European languages. The capital and largest city of Hungary is Budapest; other major cities include Debrecen, Szeged, Miskolc, Pécs, and Gyr. Various peoples, including Celts, Romans, Germanic tribes, Huns, West Slavs, and Avars, populated the area of modern-day Hungary for millennia. With the conquest of the Carpathian Basin by Hungarian grand prince rpád in the late ninth century AD, the foundations of the Hungarian state were laid. In the year 1000, his great-grandson Stephen I ascended the throne, transforming his kingdom to a Christian one. Hungary became a regional force by the 12th century, achieving its cultural and political pinnacle in the 15th century. It was partly occupied by the Ottoman Empire after the Battle of Mohács in 1526. Hungary was ruled by the Habsburgs at the turn of the 18th century, later entering the Austrian Empire to create Austria-Hungary, a major force until the early 20th century. After World War I, Austria-Hungary collapsed, and the Treaty of Trianon formed Hungary's current boundaries, resulting in the loss of 71% of Hungary's territory, 58% of its population, and 32% of ethnic Hungarians. Hungary entered the Axis Powers in World War II after a turbulent interwar era, suffering major damage and casualties. Hungary became a Soviet satellite state after WWII, resulting in the creation of the Hungarian People's Republic. Hungary became a comparatively freer, but still repressive, member of the Eastern Bloc following the failed 1956 revolution. The fall of the Eastern Bloc, and later the Soviet Union, was hastened by the destruction of Hungary's border fence with Austria. Hungary became a democratic parliamentary republic on October 23, 1989. Hungary became a member of the European Union in 2004 and of the Schengen Area in 2007. Hungary is a middle force in foreign relations, owing to its cultural and economic clout. It has a high-income economy and ranks "very high" on the Human Development Index, with universal health care and free secondary education for its residents. Hungary has made important contributions to the arts, music, literature, sports, science, and technology for many years. In 2017, it was Europe's thirteenth most popular tourist destination, with 15.8 million foreign visitors. It is a member of the United Nations, NATO, the World Trade Organization, the World Bank, the IIB, the AIIB, the Council of Europe, and the Visegrád Group.