Lithuania–Russia relations in Suvalkija, to the Soviet sphere of influence. The exchange of territories was also motivated by Soviet control of Vilnius: the Soviet Union could exert significant influence on the Lithuanian government, which claimed Vilnius to be its "de jure" capital. In the secret protocols, both Soviet Union and Germany explicitly recognized Lithuanian interest in Vilnius. Accordingly, by the Soviet–Lithuanian Mutual Assistance Treaty of October 10, 1939, Lithuania would acquire about one fifth of the Vilnius Region, including Lithuania's historical capital, Vilnius, and in exchange would allow five Soviet military bases with 20,000 troops to be established across Lithuania. After months
Lithuania July 1991, Soviet paramilitaries killed seven Lithuanian border guards on the Belarusian border in what became known as the Medininkai Massacre. On 17 September 1991, Lithuania was admitted to the United Nations. On 25 October 1992, the citizens of Lithuania voted in the referendum to adopt the current constitution. On 14 February 1993, during the direct general elections, Algirdas Brazauskas became the first president after the restoration of independence of Lithuania. On 31 August 1993, the last units of the Soviet Army left the territory of Lithuania. Since 29 March 2004, Lithuania has been part of the NATO. On 1