Rubuta ci gaba don wannan sakin layi - Soviets sun kara da'awar sassan gabashin Finland, amma gwamnatin Finland ta ki. 'Yan Soviet sun mamaye Finland
a watan Nuwamba 1939, duk da ƙarancin adadi, Finns sun riƙe Red Army a bay. Ra'ayin duniya ya goyi bayan Finland, tare da korar Soviets daga League of Nations. Abin kunya saboda rashin iyawarsu na kayar da Finns, Soviets sun sanya hannu kan yarjejeniyar zaman lafiya na wucin gadi, wanda suka karɓi rabon ƙasa daga Finland. A watan Yunin 1940, Sojojin Red sun mamaye jihohin Baltic, waɗanda aka haɗa su da ƙarfi cikin Tarayyar Soviet a watan Agusta; sun kuma mamaye kuma sun haɗu da Bessarabia da arewacin Bukovina, sassan Romania. Soviets sun nemi hana rashin amincewa a cikin waɗannan sabbin yankuna na Gabashin Turai tare da tsanantawa. Ofaya daga cikin shahararrun misalai shine kisan gillar Katyn na Afrilu da Mayu 1940, wanda aka kashe kusan membobin sojojin Poland 22,000, 'yan sanda, da masu ilimi.