Operation Barbarossa

A strategic surprise to Joseph Stalin and the Soviet Union, Operation Barbarossa was the German code name for its invasion of Russia on 22 June 1941. Stalin had believed the Molotov-Ribbentrop Pact promising nonaggression from the Germans.

Stalin's failure to prepare

Stalin received a warning document, in May 1939, about The Future Plans of Aggression by Fascist Germany, based on a German briefing obtained by Soviet spies in Warsaw. A Soviet agent first reported that Hitler planned to declare war on the Soviet Union in March 1941, and refined the estimate, by February 28, to May 20.

This intelligence was corroborated by sources in Bucharest, Budapest, Sofia and Rome, to say nothing of the information provided by the spy Richard Sorge (code-named Ramsay) in Tokyo in which the authors detail the undercover operations of the spy ring headed by Richard Sorge and Hotsumi Ozaki which transmitted highly secret information from Tokyo to the Soviet Union between 1933 and 1941. On April 17 a Prague informant predicted a German invasion in the second half of June. The precise date and time of the invasion were revealed by a reliable source in Berlin fully three days before the Germans attacked.

All of this Stalin ignored. Typically, he scrawled on the bottom of the Prague report: English provocation! Investigate! On May 19, Sorge predicted that 150 divisions were being readied by the Germans for an invasion of the Soviet Union. Stalin retorted with an expletive.

The result was that literally nothing was done to prepare for the German assault, which was code-named Operation Barbarossa. Soviet planes were not camouflaged. Troops were not in defensive positions; indeed they were ordered not to occupy such positions, for fear of provoking the Germans. Worse, Stalin responded to the gathering storm with yet another purge of suspected threats to his own authority.