Temporary capital of Lithuania during the invasion of Poland, to Lithuania according to the Soviet–Lithuanian Mutual Assistance Treaty. Since then Vilnius has been the capital of the Lithuanian SSR and then independent Lithuania. Lithuania refused to have diplomatic relations between Poland and Lithuania until the ultimatum of 1938. Railroad traffic, telegraph lines or even mail could not cross the Polish–Lithuanian border. Lithuania continued to declare Vilnius as its capital in all official documents, including the constitution. Since the city was controlled by Poland, all Lithuanian authorities were transferred to the city of Kaunas, which became the seat of the government. To reconcile reality with
1922 Republic of Central Lithuania general election a mere fraction of the total population (about 2–3% of the population, according to Russian 1897 and German 1916 censuses). The Lithuanians nonetheless believed that their historical claim to the city (former capital of the Grand Duchy of Lithuania) had precedence and refused to recognize any Polish claims to the city and the surrounding area. The League of Nations mediated the dispute and strongly advocated a plebiscite where the local population would vote to be incorporated either into Poland or Lithuania. However, neither Poland nor Lithuania wanted the vote. Poland had control of the territory and saw no reason to