Short answers, pulled from the story.
The Winter War began on the 30th of November 1939, when the Soviet Union invaded Finland with 21 divisions totalling 450,000 men. It ended three and a half months later with the signing of the Moscow Peace Treaty on the 13th of March 1940.
The Soviet Union sought to move the Finnish border on the Karelian Isthmus farther from Leningrad, which was only 32 kilometres from Finland, and to secure strategically important islands and peninsulas. Historians disagree on whether Stalin intended full conquest of Finland or merely territorial security; the formation of a puppet Finnish government on the 1st of December 1939 and the Molotov-Ribbentrop Pact's secret protocols are cited as evidence of broader ambitions.
Under the Moscow Peace Treaty signed on the 13th of March 1940, Finland ceded approximately 9 percent of its territory to the Soviet Union. Soviet gains included substantial lands along Lake Ladoga and territories further north, exceeding even the demands the Soviets had made before the war.
The Battle of Raate Road was part of the Battle of Suomussalmi, in which Finnish Colonel Hjalmar Siilasvuo and his 9th Division encircled and destroyed approximately 14,000 Soviet troops from the 44th and 163rd Rifle Divisions. Soviet casualties numbered between 7,000 and 9,000; Finnish casualties totalled 400. The action is studied as an example of effective tactics against a numerically superior force.
Simo Häyhä was a Finnish sniper who fought in the Battle of Kollaa and was credited with more than 500 kills during the Winter War. Finnish media dubbed him "the White Death." The Battle of Kollaa, where he served, lasted until the end of the war and produced the legendary motto "Kollaa holds."
The poor performance of the Red Army during the Winter War encouraged German Chancellor Adolf Hitler to believe that an attack on the Soviet Union would succeed, and it confirmed negative Western views of Soviet military capability. Germany launched Operation Barbarossa in June 1941, approximately 15 months after the Moscow Peace Treaty ended the Winter War.