Fund for their housing and education. A 1935 estimate puts the number of refugees to 20,000. MASSR had a mixed Ukrainian (46%) and Moldovan (32%) population, which was estimated at 545,500. Its area was 8,677 km2 and included 11 raions on the left bank of Dniester. Under Stalinist rule, populations who were not Ukrainian, Russian, or Romanian were pressured to Russify, and their numbers would decline further. After a brief initial period of liberalization and freedom, groups such as the Poles in the Soviet Union were subject to harassment, dispersal and mass terror. This trend increased in the late 1930s, as a result of the 1937-8 Polish Operation of the NKVD as well as the ceasing of educational instruction in the Moldavian ASSR for all non-Romanians populations in their native languages which was replaced by Ukrainian and Russian. According to the 1926 Soviet census, the Republic had a population of 572,339, of which: While the creation of ethnic-based autonomous polities was a general policy of the Soviets at that time, with the creation of the Moldavian ASSR, the Soviet Union also hoped to bolster its claim to Bessarabia. Soviet authorities declared the "temporarily occupied city of Kishinev" as de jure capital of the ASSR. At that time, the population of Moldavian ASSR was 48% Ukrainian, 30% Romanian/Moldavian, 9% Russian, and 8.5% Jewish. In 1940, 6 of the 14 districts of MASSR were included in the new created Moldavian SSR, together with a part of Bessarabia. According to the Soviet census of 1926, in the districts of Camenca, Rîbniţa, Dubăsari, Grigoriopol, Tiraspol and Slobozia, a territory roughly similar with today's Transnistria, there were 44,11% Moldavians (Romanians), 27,18% Ukrainians, 13,69% Russians, 8,21% Jews, 3,01% Germans etc. World War II The Moldavian SSR, which was set up by a decision of the Supreme Soviet of the USSR on 2 August 1940, was formed from a part of Bessarabia taken from Romania on June 28, following the Molotov-Ribbentrop pact, where the majority of the population were Romanian speakers, and a strip of land on the left bank of the Dniester in the Ukrainian SSR, which was transferred to it in 1940 (the strip being roughly equivalent to the territory of today's Transnistria). In 1941, after Axis forces invaded Bessarabia in the course of the Second World War, they advanced over the Dniester river. Romania controlled the entire region between Dniester and Southern Bug rivers,