Operation Unthinkable was the name of the British Chiefs of Staff plan at the end of WWII in Europe. It involved two related possible future war plans against the Soviet Union. While the plans were never approved or implemented, the creation of the plans had been ordered by the British Prime Minister Winston Churchill (1874-1965) in May 1945.

One plan called for a surprise attack on the Soviet forces stationed in Germany with the expressed purpose to “impose the will of the Western Allies” on the Soviet’s. The hypothetical date for the start of the Allied invasion of Soviet-held Europe was scheduled for 1 July 1945. The plan assumed a surprise attack of up to 47 British and American divisions in the area of the city of Dresden, in the middle of the Soviet lines.

The British planners realized that without massive American help Britain would probably fail.

The code name was then reused instead for a second plan, which was a defensive scenario in which the British were to defend against a Soviet drive towards the North Sea and the Atlantic following the withdrawal of the American forces from the Continent. Both plans were never shared with the Americans nor with any other entity. Both plans were highly secret and were not made public until 1998- although a British spy for the Soviets, Guy Burgess (1911-1963), had passed on some details at the time.

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