Hungary is a landlocked country in Central Europe. It is situated in the Carpathian Basin and is bordered by Slovakia to the north, Ukraine, and Romania to the east, Serbia, and Croatia to the south, Slovenia to the southwest and Austria to the west. The country's capital, and largest city, is Budapest. Hungary is a member of the European Union, NATO, the OECD, the Visegrád Group, and the Schengen Agreement. The official language is Hungarian, also known as Magyar, which is part of the Finno-Ugric group and is the most widely spoken non-Indo-European language in Europe.Following periods of successive habitation by Celts, Romans, Huns, Slavs, Gepids, and Avars, the foundation of Hungary was laid in the late 9th century by the Hungarian grand prince Árpád, whose great-grandson Saint Stephen I ascended to the throne in 1000 AD. The Kingdom of Hungary existed for 946 years,and at various points was regarded as a major political power in Europe, as well as one of the cultural centres of the Western world. After about 150 years of partial Ottoman occupation (1541–1699), Hungary was integrated into the Habsburg Monarchy, and later constituted half of the Austro–Hungarian Empire (1867–1918).