On 30 November 1939, the Soviet Union launched a war against Finland after a futile year and a half campaign to persuade the Finnish government to cede territory to the Soviet Union and give up some sovereignty by conceding specific military and political favors. The Finnish Army, facing Red Army tanks in what came to be known as the Winter War, borrowed the design of an improvised incendiary device that had been used for the first time[2] in the just-concluded Spanish Civil War (July 1936–April 1939)
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During the Winter War, the Soviet air force made extensive use of incendiaries and cluster bombs against Finnish troops and fortifications. When Soviet People's Commissar for Foreign Affairs Vyacheslav Molotov claimed in radio broadcasts that the Soviet Union was not dropping bombs but rather delivering food to the starving Finns, the Finns started to call the air bombs Molotov bread baskets.[4] Soon they responded by attacking advancing tanks with "Molotov cocktails" which were "a drink to go with the food". At first, the term was used to describe only the burning mixture itself, but in practical use the term was soon applied to the combination of both the bottle and its contents. This Finnish use of the hand- or sling-thrown explosive against Soviet tanks was repeated in the subsequent Continuation War between the two countries.