The Finnish Winter War took place from November 30, 1939, to March 13, 1940, between Finland and the Soviet Union. The conflict began when the Soviet Union invaded Finland, seeking to gain territory and secure its northwestern borders. Despite being heavily outnumbered, Finnish forces utilized their knowledge of the harsh winter conditions and guerrilla tactics to resist the invasion effectively. The war ended with the Moscow Peace Treaty, which resulted in Finland ceding about 10% of its territory to the Soviet Union. Although Finland lost land, the conflict boosted national unity and military reputation, demonstrating the resilience of the Finnish people against a larger adversary.