Before World War I Finland was part of Imperial Russia. As part of realm of the Czars, Finland chafed under its rule. After the war Finland, along with Poland, Lithuania, Latvia, and Estonia, were carved out of the old empire and made into autonomous nations.
The founder of the Soviet Union, Vladimir Lenin, was too concerned with issues at home to reclaim the territories. His successor felt it was time. In October 1939 Finlands emissaries were summoned to Moscow. Stalin gave Finland an ultimatum: move your border so Leningrad was not within artillery range, demilitarize the Karelian Isthmus, cede islands, and allow ports to be leased indefinitely. The Finns were willing to concede on these points; however, the Soviets also wanted basing rights for aircraft and warships in the port of Hango. The Finns demurred; the Soviets broke off negotiations on November 13, 1939. The Finns mobilized, and the Soviets attacked all along the border on November 30. Helsinki was bombed.
At first glance, it seemed the Finns were outmatched. But their small army of 200,000, facing overwhelming Soviet numbers, invented the Molotov Cocktail gasoline in glass jars to stop Red Army tanks. Stalins purges of his forces also began to take their toll. The Red Army failed to be inventive or highly mobile. Timid not because of cowardice, but because of a fear of their own government, the army also had large numbers of unmotivated conscripts. Winter equipment was not available to the Red Army and they froze in the forests, wary of attack from any direction. Stalin was stunned by the mounting losses of his army.
The Finns became masters of hit-and-run tactics. Soviet thrusts would be cut off and surrounded, and if they were lucky enough to claw their way back to Soviet lines they would suffer heavy casualties. Meanwhile, worldwide indignation was directed at the Soviets for their aggression. Late in coming, even the American public was outraged by the Soviet invasion. Roosevelt extended ten million in aid. The French under Daladier also began sending money and considered military action against the Soviets. Several nations offered monetary support.
Stalin was determined to win the war with the Finns before foreign aid could have any lasting effect. He brought up more soldiers and many more artillery guns, and began a new offensive on February 1, 1940. By March 7, the Finns asked for an armistice. Stalin accepted on March 12.
In France, the Daladier government fell after promising to prevent the Finns from succumbing to their foes. A new government under Reynaud was formed and pledged to prosecute the war in the West against Germany with even more vigor.
Finlands border with the Soviet Union was set back to the time of Peter the Great in 1721. She lost the Karelian Ithmus. Months later, she let German troops pass through on the way to invade Norway. Many units remained, and jumped into the Soviet Union from Finland in June 1941. Technically neutral, strong anti-Soviet feeling led the Finns to allow the troops to advance.
Britain declared war on Finland on December 6, 1941. The United States, recognizing that Finland was not an ally, seized Finnish ships. Throughout the war, German planes attacked Murmansk and Archangel from Finnish airfields. German and Soviet units engaged frequently in Finland. Finland was clearly on the side of the Axis.
In February 1944, US secretary of State Cordell Hull informed Finland that continued support of Germany would result in serious consequences. As Soviet soldiers advanced in September 1944, Finland sought an armistice with the Allies. She declared war on the Axis on March 3, 1945.
After the war, the Finns were forced to give up much of the same territory that she lost in 1940.