# Soviet Union attacks Finland, opening the Winter War Date: 1939 ## The fact On 30 November 1939, after the staged Mainila incident and Finnish refusal to cede bases and Karelian territory, the Red Army attacked Finland. The League of Nations expelled the USSR in December. The March 1940 Moscow peace took the Karelian Isthmus and other areas. Later speeches, the cult, and measured deaths are not mixed into this Fact. ## Context The secret protocol had assigned Finland to the Soviet sphere. The Terijoki puppet government of Kuusinen failed. Shared responsibility with the Politburo, Sovnarkom, NKVD, front commands, and later the State Defence Committee is part of the record. Sharing is not a reason to drop [Stalin](/people/joseph-stalin)’s signature or chairmanship, and it is not a reason to treat every local killing as a personal handwriting sample. ## Evidence and sources Avalon and League records document the attack and expulsion. Britannica and Trotter/Edwards reconstruct the campaign. Peace-treaty territorial cessions are official. Where later commissions publish death or deportee estimates, those estimates are attributed to the commission, not invented as a Factrail original count. ## Significance Strengthens armed-conflict intensity and later [territorial-revisionism](/drivers/territorial-revisionism). Direct contribution. High confidence. A decree does not harvest grain, a pact does not fire a rifle, and a conference protocol does not occupy a city by itself. Implementation, if dated, is a later Fact. Mixed welfare effects are separate paths. ## What is established and what is not Established: the USSR attacked Finland on 30 November 1939 and later annexed territory by treaty. Not established: that Mainila was a genuine Finnish attack. What would change the picture: a contradictory original protocol with a different date or signatory; a demonstrated forgery of the cited order; or a measured series that can be argued, with lag and alternatives, as a consequence of this instrument rather than of war, weather, or unauthorized local action. The documentary limit is the same for every Stalin instrument in this dossier. Central files can show that an order was issued; they cannot, by themselves, reconstruct every raion’s implementation. Memoir and literary evidence (Solzhenitsyn, Shalamov, Grossman) is used here only as independent texture, never as the sole causal source. Soviet published statistics of the 1930s are treated as official claims with known incentives to over-report industrial output and under-report famine. Post-1956 party revelations, the 1991–92 archival openings, the 2010 Russian [State Duma](/organizations/state-duma) statement on Katyn, Ukrainian Holodomor statutes, and USHMM/Wilson Center document publications are later independent or successor-state records. They do not convert this Fact into a personality score. They do not cancel the original instrument. Readers who want the welfare path should open the named driver, then the indicator that driver already reaches, rather than treating the portrait as the mechanism. The documentary limit is the same for every Stalin instrument in this dossier. Central files can show that an order was issued; they cannot, by themselves, reconstruct every raion’s implementation. Memoir and literary evidence (Solzhenitsyn, Shalamov, Grossman) is used here only as independent texture, never as the sole causal source. Soviet published statistics of the 1930s are treated as official claims with known incentives to over-report industrial output and under-report famine. Post-1956 party revelations, the 1991–92 archival openings, the 2010 Russian State Duma statement on Katyn, Ukrainian Holodomor statutes, and USHMM/Wilson Center document publications are later independent or successor-state records. They do not convert this Fact into a personality score. They do not cancel the original instrument. Readers who want the welfare path should open the named driver, then the indicator that driver already reaches, rather than treating the portrait as the mechanism. ## People - Joseph Stalin: https://factrail.ai/people/joseph-stalin ## Drivers - Armed-Conflict Intensity: https://factrail.ai/drivers/sec-armed-conflict-intensity ## Sources - https://www.britannica.com/event/Russo-Finnish-War - https://avalon.law.yale.edu/wwii/ussr03.asp ## Methodology https://factrail.ai/methodology Canonical: https://factrail.ai/facts/su-winter-war-1939