Lithuanians are related to tribes who moved from the east and settled in the region a few thousand years ago, which later formed different linguistic groups, including Semigallians, ancient Prussians, Latvians and Lithunians, which all spoke languages that belonged to the Indo-European linguistic family. However, through assimilations and conquests of the Baltic territories in the course of history, only the Lithuanians and Latvians languages and cultures have survived to this day.
In the early 13th century, Lithuania began to have the semblance of a state when the tribes united to fend off attacks by the crusading Teutonic Knights from Germany, who vanquished the ancient Prussians to form a new Prussian state. For the next century, Lithuania extended its influence to reach as far as the Black Sea and created a kingdom with Lithuanians, Slavs Orthodox Christians and pagans. Still under constant pressure from the Teutonic Knights, Lithuania formed a union with Poland around the 1380s and converted into Christianity. In 1410, the union defeated the Teutonic Knights and halted German expansion.
For the next four centuries, Lithuania gradually became dominated by Poland and the Polish church, until 1795 when the Russian-Prussian-Hapsburg alliance made the third and final partition of Poland and Lithuania became a province of Russia. Since then Lithuanian culture, religion, education and language were suppressed. Starting from the 1880s, nationalist movements previously suppressed came to the surface and during the 1905 Russian Revolution demanded independence, but was rebuffed when the revolution collapsed.
With the defeat of the German and Russian Empires after WW I, Lithuania declared its independence in February 1918. However, in the next few years, it had to fight wars with Poland, some German militias and the Russian Red Army, all to defend its independence. In 1920, Soviet Russia signed a peace treaty formally recognising the Lithuanian state. However, Poland still held onto Lithuanian territory including the province of Vilnius until 1939.
Until the WW II, Lithuania went through a period of instability caused by the lack of a well established democratic tradition and, at least initially, a high percentage of illiteracy, while at the same time embarked on the process of nation building. The 1939 Nazi-Soviet Nonaggression Pact led to the annexation of Lithuania by the Soviets in that year and Vilnius was returned from Poland. The Soviets were soon replaced by the Nazis. During both occupations, large numbers of Lithuanians were killed or deported to concentration camps.
Soviet Russia re-established its rule over Lithuania after WW II, but continued to face periodic dissident movements expressed in various ways. At the same time, Russification of the country intensified. It was only in the late 1980s when reforms introduced by Mikhail S. Gorbachev in the Soviet Union finally led to Lithuania regaining its sovereignty in 1991.