Lithuania declared independence from the former Russian Empire on February 16, 1918. In March the Bolsheviks signed the Treaty of Brest-Litovsk and renounced any claims to the Baltic states, including Lithuania. Ober Ost, the German occupying authority, did not allow Lithuania to establish government institutions, organize military or police forces, or attempt to define its borders. Lithuanian independence remained a largely unrealized political declaration. That changed when Germany surrendered in November 1918. Lithuanians hurriedly adopted a provisional constitution, formed a government, and started organizing an army.
Soviet Russia denounced the Treaty of Brest-Litovsk and renewed its interest in the Baltic region. In late December 1918, Lithuanian territory was invaded by Bolshevik forces, pursuing the retreating Germans. That marked the beginning of the Lithuanian Wars of Independence and the Polish–Soviet War. Within a month Soviet forces controlled large portions of northern and eastern Lithuania. The advance was stopped only with help from German volunteers. In Vilnius, the Bolsheviks proclaimed a puppet Soviet government, led by Vincas Mickevičius-Kapsukas. In February 1919 the Lithuanian SSR was merged with the Byelorussian SSR, to form Litbel. The entity was short-lived as Poland and Lithuania successfully counterattacked. Vilnius, the historic capital of Lithuania, was seized by the Poles in April. The last Bolsheviks were pushed from Lithuanian territory at the end of August. The entire territory of Litbel was taken by September 1919 and it ceased to exist.