The Baltic states or the Baltic countries is a geopolitical term encompassing Estonia, Latvia, and Lithuania. All three countries are members of NATO, the European Union, the Eurozone, and the OECD. The three sovereign states on the eastern coast of the Baltic Sea are sometimes referred to as the "Baltic nations", less often and in historical circumstances also as the "Baltic republics", the "Baltic lands", or simply the Baltics.

The Grand Duchy of Lithuania was a sovereign state in northeastern Europe that existed from the 13th century, succeeding the Kingdom of Lithuania, to the late 18th century, when the territory was suppressed during the 1795 partitions of Poland–Lithuania. The state was founded by Lithuanians, who were at the time a polytheistic nation of several united Baltic tribes from Aukštaitija, which by 1440, became the largest European state controlling an area from the Baltic Sea in the north to the Black Sea in the south.