The Winter War came to Ilomantsi on 30 November  1939. The Red Army’s 155th Division supported by tanks and artillery rolled over the villages and settlements in the eastern part of the municipality. Möhkö village was lost on 9 December . The sky glowed fiery red when the retreating Finnish troops set houses on fire. 

On 10 December  the attack was halted on the Oinassalmi–Kallioniemi line where bodies of water favored the defenders. 

On 13 and 14 December a decisive battle was fought near Lake Taivallampi, ten kilometres from Ilomantsi parish village. Meanwhile, six kilometres to the north of the village, the enemy had reached Kallioniemi but was held by the defenders. 

The situation began to change when Russian troops crossed the frozen Lake Karpanjärvi to break through the defenders’ rear. The Finnish 11th Independent Battalion, which had recently been involved in heavy fighting, was camped near Taivallampi. Its commander, Captain Viljo Kivikko, was ordered to seek out and destroy the infiltrators. 

The Soviets’ position was revealed when they opened fire at a supply column heading toward Oinassalmi at 14:00 on 14 December  near Taivallampi. All telephone lines in the area were simultaneously cut off. The situation was becoming critical. The Finnissh forces fought fiercely through the night. The next morning at 06:00, Captain Kivikko reported that two enemy battalions had been practically annihilated and the road connection from Oinassalmi to the parish village was restored. 

It is widely estimated that 600 Red Army troops were involved in the battle of Taivallampi. Less than 40 of them became prisoners-of-war. The attacking force was decimated almost to the last man, including their commander, Captain Koslov. The soldiers are buried in unmarked graves in nearby forests.

The Finnish forces’ successes at Taivallampi and on the other Fronts of the Winter War were the result of multiple factors. The Red Army was generally ill-equipped and did not have camp gear such as cardboard or canvas tents and field stoves. Many troops were unaccustomed to winter conditions with snow and sub-zero temperatures, at least to the extent that would have been needed for survival in forested terrain in wintertime. With the exception of a small number of special units, the Russian forces also lacked skis and skiing skills.