Soviet deportations from Lithuania were a series of 35 mass deportations carried out in the Lithuanian SSR, a republic of the Soviet Union, in 1941 and 1945–1952. At least 130,000 people, 70% of them women and children, were forcibly transported to labor camps and other forced settlements in remote parts of the Soviet Union, particularly in the Irkutsk Oblast and Krasnoyarsk Krai. Among the deportees were about 4,500 Poles. These deportations do not include Lithuanian partisans or political prisoners (approximately 150,000 people) deported to Gulags (prison camps). Deportations of the civilians served a double purpose: repressing resistance to Sovietization policies in Lithuania and providing free labor in sparsely inhabited areas of the Soviet Union. Approximately 28,000 of Lithuanian deportees died in exile due to poor living conditions. After Stalin's death in 1953, the deportees were slowly and gradually released. The last deportees were released only in 1963. Some 60,000 managed to return to Lithuania, while 30,000 were prohibited from settling back in their homeland. Similar deportations took place in Latvia, Estonia, and other parts of the Soviet Union (see Soviet deportations from Estonia and population transfer in the Soviet Union). Lithuania observes the annual Mourning and Hope Day on June 14 in memory of those deported.
In August 1939, Nazi Germany and Soviet Union signed the Molotov–Ribbentrop Pact whereby dividing Eastern Europe into spheres of influence. The Baltic states (Lithuania, Latvia and Estonia) became part of the Russian sphere. The Soviet Union began preparations for the occupation and incorporation of these territories. First, it imposed mutual assistance treaties by which the Baltic states agreed to allow military bases for Soviet soldiers within their territory. Further steps were delayed by Winter War with Finland. By spring 1940, the war was over and Soviet Union increased its rhetoric accusing the Baltics of anti-Soviet conspiracy. Lithuania received Soviet ultimatum on June 14, 1940. Almost identical ultimatums to Latvia and Estonia followed two days later. Soviet Union demanded to allow an unlimited number of Soviet troops to enter the state territory and to form a more pro-Soviet government. The Soviets followed semi-constitutional procedures while transforming independent Baltic states into the soviet socialist republics. They formed pro-Soviet People's Governments and held show elections to People's Parliaments. The annexation of the Lithuanian SSR, Latvian SSR, and Estonian SSR was completed by August 6, 1940.