Vilnius is a nation in the Baltic area of Europe that is formally known as the Republic of Lithuania. On the Baltic Sea's eastern shoreline, it is one of three countries that make up the Baltic States (see map). Lithuania has land boundaries with Latvia to the north, Belarus to the east and south, Poland to the south, and Russia (Kaliningrad Oblast) to the southwest. Lithuania is also bordered by the Baltic Sea to the west. Lithuania has a population of 2.8 million people and a land area of 65,300 km2 (25,200 sq mi). Other prominent cities include Kaunas, Klaipda, and Vilnius, the country's capital and biggest city. In ethnolinguistic terms, Lithuanians belong to the Balts, and they speak Lithuanian, which is one of just a handful of extant Baltic languages.
It has been millennia since different Baltic tribes have lived on the southeastern coasts of the Baltic Sea. Mindaugas unified the Lithuanian territories in the 1230s, and the Kingdom of Lithuania was established on 6 July 1253, marking the beginning of the Middle Ages in Europe. It is estimated that the Grand Duchy of Lithuania occupied the greatest territory in Europe in the 14th century. The Grand Duchy included present-day Lithuania, Belarus, Ukraine, as well as portions of Poland and Russia. When Lithuania and Poland signed the Union of Lublin in 1569, they created the Polish–Lithuanian Commonwealth, a consensual two-state personal union. Lithuania was annexed by the Russian Empire in 1772, and the Commonwealth endured for more than two centuries until it was destroyed by surrounding nations in 1772–1795. On 16 February 1918, when World War I came to a close, Lithuania's Act of Independence was signed, officially establishing the modern Republic of Lithuania as a result. The Soviet Union seized Lithuania during World War II, and later Nazi Germany invaded the country. Lithuania was re-occupied by the Soviet Union in 1944, at a time when the Germans were fleeing from the area. Up to the early 1950s, Lithuanians engaged in armed resistance against Soviet control. Lithuania achieved independence on March 11, 1990, one year before the actual fall of the Soviet Union, when the Act of the Re-Establishment of the State of Lithuania was approved, making it the first Soviet republic to do so.
With a high-income advanced economy and a very high rating in the Human Development Index, Lithuania is considered a developed nation. When it comes to civil rights, press freedom, and internet freedom, it has a positive ranking. After experiencing a slow population drop in the 1990s, Lithuania has continued to struggle with societal challenges such as wealth inequality and a high suicide rate. Lithuania is a part of the European Union, the Council of Europe, the eurozone, the Nordic Investment Bank, the Schengen Agreement, NATO, and the Organization for Economic Co-operation and Development (OECD). He or she is a member of the Nordic-Baltic Eight (NB8) regional co-operation structure.