During the last days of February 1940 the Finnish troops were replaced with the Swedish, Norwegian and Danish volunteers of the Stridsgruppen SFK.

[2] The Soviet 14th Army was tasked with invading Finland between Kuhmo and Salla and cutting the country in half by advancing to the shores of the Gulf of Bothnia.

As part of the 14th Army's offensive, the 122nd Rifle Division, having arrived from Poland on 8 November 1939, was supposed to capture Salla and Kemijärvi and advance to Rovaniemi within two weeks, from where it would continue to Tornio near the Finnish border with Sweden.

[6] The improvements in Soviet infrastructure and demographics near the border that made it possible to supply 40,000 troops in the region had little effect on Finnish operational planning in northern Finland.

The Finnish general staff did not believe the Soviets would launch a major offensive from the White Sea region to Finland.

The Finnish general staff considered the force insufficient for even this mission, but could not spare any more troops from the more important Karelian Isthmus.

In December 1939 the lakes and swamps were not yet sufficiently frozen over to support motor vehicle movement but this became irrelevant as the winter progressed and the temperature dropped to -40°, which also made military operations more difficult.

From 11 December 1939 onward the Finnish troops were part of the Lapland Group (Lapin Ryhmä) which was commanded by Major General Kurt Martti Wallenius.

On 13 March, the last day of the war, the Soviets initiated a major fire preparation with artillery, aircraft and infantry weapons as part of a planned renewal of offensive operations towards Rovaniemi.