Lithuania, officially the Republic of Lithuania is a country in Northern Europe. It is the largest of the three Baltic states and is situated east of Sweden and Denmark, along the southeastern shore of the Baltic Sea. It borders 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 3 million as of 2013, and its capital and largest city is Vilnius. The Lithuanians are a Baltic people, and the official language, Lithuanian, is one of only two living languages (together with Latvian) in the Baltic branch of the Indo-European language family.

For centuries, the southeastern shore of the Baltic Sea was inhabited by various Baltic tribes. In the 1230s the Lithuanian lands were united by Mindaugas, the King of Lithuania, and the first unified Lithuanian state, 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: present-day Lithuania, Belarus, Ukraine, and parts of Poland and Russia were the territories of the Grand Duchy. With the Lublin Union of 1569, Lithuania and Poland formed a voluntary two-state union, the Polish–Lithuanian Commonwealth. The Commonwealth lasted more than two centuries, until neighboring countries systematically dismantled it from 1772 to 1795, with the Russian Empire annexing most of Lithuania's territory.

As World War I neared its end, Lithuania's Act of Independence was signed on 16 February 1918, declaring the establishment of a sovereign State of Lithuania. Starting in 1940, Lithuania was occupied first by the Soviet Union and then by Nazi Germany. As World War II neared its end in 1944 and the Germans retreated, the Soviet Union reoccupied Lithuania. On 11 March 1990, a year before formal break-up of the Soviet Union, Lithuania became the first Soviet republic to declare the restoration of independent State of Lithuania.