Lithuania (Lietuva ), officially the Republic of Lithuania (Lietuvos Respublika), is a country in the Baltic region of Europe. Lithuania is one of the Baltic states. The country is situated along the southeastern shore of the Baltic Sea, to the southeast of Sweden and Denmark. It is bordered by Latvia to the north, Belarus to the east and south, Poland to the south, and Kaliningrad Oblast (a Russian exclave) to the southwest. Lithuania has an estimated population of 2.8 million people and its capital and largest city is Vilnius. Other major cities are Kaunas and Klaipėda. Lithuanians are Baltic people. The official language, Lithuanian, is one of only two living languages in the Baltic branch of the Indo-European language family, the other being Latvian. For centuries, the southeastern shores of the Baltic Sea were inhabited by various Baltic tribes. In the 1230s, the Lithuanian lands were united by Mindaugas and the Kingdom of Lithuania was created on 6 July 1253. During the 14th century, the Grand Duchy of Lithuania was the largest country in Europe; to declare itself independent, resulting in the restoration of an independent State of Lithuania. Lithuania 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. Lithuania is a member of the European Union, the Council of Europe, eurozone, Schengen Agreement, NATO and OECD. It is also a member of the Nordic Investment Bank, part of Nordic-Baltic cooperation of Northern European countries, and is classified as a Northern European country by the United Nations.