What did Hitler order in Directive No. 21?

In Directive No. 21, issued on December 18, 1940, Adolf Hitler ordered that the German armed forces must be prepared to crush the Soviet Union in a quick campaign before the conclusion of the war against England.1

This directive, titled "Case Barbarossa," formalized Hitler’s long-standing intention to overthrow the Soviet regime. Driven by his anti-Bolshevik convictions and growing suspicion of Joseph Stalin’s intentions—particularly following Soviet territorial expansions in the Baltic states and Romania—Hitler sought to eliminate the Soviet threat to secure Germany’s rear. Although the invasion was originally scheduled for mid-May 1941, the necessity of campaigns in Yugoslavia and Greece forced a postponement to late June 1941. Despite the concerns of his generals regarding the risks of a two-front war and the logistical challenges of the campaign, Hitler remained convinced that the Red Army could be defeated within a few months.21