Thetimeline of the Winter War is a chronology of events leading up to, culminating in, and resulting from theWinter War. The war began when theSoviet Union attackedFinland on 30 November 1939 and it ended 13 March 1940.
21 March 1918: Finnish nationalist volunteers launch the militaryViena expedition, attempting to annex Karelia to Finland; the expedition ultimately failed.
15 May 1918: Finnish Civil War ends with a victory by the White Guards underC.G.E. Mannerheim.
23 January 1919: The Finnish population in Ingria rebels from Soviet Russia, creating theRepublic of North Ingria, which seeks to join Finland. The short-lived state is later reincorporated into Russia.
21 April 1919: Finnish armed nationalist volunteers launch theAunus expedition, attempting to annex Karelia to Finland. Due to lack of significant support from the local population and Soviet resistance, the expedition was ultimately defeated. Finnish historiography does not consider these expeditions and rebellions to be wars, while Russian historiography considers them as military interventions, calling them the "First Soviet–Finnish War."
14 October 1920: Soviet Russia and Finland sign theTreaty of Tartu, which provides for mutual de jure recognition and a settlement of the border. The harbor ofPetsamo is ceded to Finland in exchange for the parishes ofRepola andPorajärvi, which had briefly seceded from Russia to Finland previously.
October 1921: TheEast Karelian Uprising begins against Soviet Russia. Armed Finnish volunteers soon join to take part in the fighting. The uprising is ultimately defeated; the rebels cross the border to refuge in Finland.
21 January 1932: The Soviet Union and Finland negotiate anon-aggression pact.
24 August 1939:Russo-German non-aggression pact signed. Secret protocol places the Baltic region and Finland within the Soviet Union's sphere of interest.
11–12 October 1939: Finnish delegation meetsV.M. Molotov andJ.V. Stalin in Moscow, and receives demands of concessions. The Soviet demands include the secession of territory in the Karelian Isthmus, islands in the Gulf of Finland, and theRybachy Peninsula, as well as the lease of a naval base atHanko. In return, they offer to secede the municipalities ofRepola andPorajärvi, making up twice as much territory as their demands of Finland. The offer divides the Finnish government, who ultimately reject it.
23 October 1939: The Finnish make a counteroffer, offering the town of Terijoki, much smaller than Soviet demands.
31 October 1939: Molotov makes a speech before theSupreme Soviet of the Soviet Union, publicly announcing the Soviet demands and offers.
13 November 1939: The Finnish delegation returns home, ending negotiations.
26 November 1939: The Soviets stage theShelling of Mainila, bombarding a Soviet village in order to obtain a pretext for war against Finland.
28 November 1939: The Soviets withdrawn from the non-aggression pact, using their staged incident as a pretext.
29 January 1940: The Soviets abandon their puppetTerijoki government and recognize the Finnish government as the legitimate government of Finland. The Soviets inquire what land Finland would be willing to cede as part of a peace deal.
18 August 1940: After the Germans obtain troop transit rights through Finland, the first German troops arrive in the port of Vaasa. Ultimately, five German army divisions deploy in Northern Finland for the planned invasion of Soviet Russia.
January 1941: The Soviets make demands regarding the mining district and port ofPetsamo, rejected by Finland with the support of Germany.
January 1941: The Germans inform Finland of their plans for their invasion of the Soviet Union; military leaders of the two countries begin planning together for the invasion.
15 June 1941: The Finnish army begins mobilization in preparation for an attack on the Soviet Union in conjunction with Germany.
21 June 1941: Finnish troops concentrate at the Finnish–Soviet border.
