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After reoccupying the Baltic states, the Soviets implemented a program of sovietization, which was achieved through large-scale industrialisation rather than by overt attacks on culture, religion or freedom of expression.[27] The Soviets carried out massive deportations to eliminate any resistance to collectivisation or support of partisans.[28] Baltic partisans, such as the Forest brothers, continued to resist Soviet rule through armed struggle for a number of years.[29] The Soviets had previously carried out mass deportations in 1940–41, but the deportations between 1944–52 were even greater.[28] In March 1949 alone, the top Soviet authorities organised a mass deportation of 90,000 Baltic nationals.[30]
The total number deported in 1944–55 has been estimated at over half a million: 124,000 in Estonia, 136,000 in Latvia and 245,000 in Lithuania. The deportees were allowed to return after Nikita Khrushchev's secret speech in 1956 denouncing the excesses of Stalinism, however many did not survive their years of exile in Siberia.[28] After the war, the Soviets outlined new borders for the Baltic republics. The Lithuanian SSR gained the regions of Vilnius and Klaipėda while the Russian SFSR annexed territory from the eastern parts of the Estonian SSR (5% of prewar territory) and Latvian SSR (2%).[28]