The massive invasion that changed the course of the Second World War

History · Published 29 September 2026 Swipe more like this →

In short: In June 1941, Nazi Germany launched the largest military offensive in human history. While the initial blitzkrieg shattered Soviet armies, a series of intelligence failures and a brutal, early winter transformed a lightning strike into a devastating war of attrition.

Originally codenamed Operation Fritz, the invasion was renamed Operation Barbarossa after the Holy Roman Emperor Frederick Barbarossen. Driven by Adolf Hitler's profound anti-Bolshevism, the campaign aimed to seize agricultural and mineral resources, specifically targeting the oil fields of the Caucasus and the territories of Ukraine and Byelorussia. The German High Command, led by figures such as Walther von Brauchitsch and Franz Halder, believed they could conquer the European portion of Russia—up to a line between Arkhangelsk and Astrakhan—within just two or three months.

The German forces were formidable, deploying roughly 150 divisions and 3 million men, including 19 panzer divisions and 3,000 tanks. However, the invasion faced critical setbacks. A five-week delay, caused by the necessity of invading Yugoslavia and Greece in April 1941, meant the campaign hit the Russian winter earlier than expected. Furthermore, German intelligence significantly underestimated Soviet strength. While the Germans anticipated only about 200 available Soviet divisions, the Red Army actually brought up more than 200 fresh divisions by mid-August, reaching a total of 360.

The human cost was staggering. The operation involved approximately 10 million combatants during its opening phase, with casualties exceeding 8 million by early December 1941. Beyond the battlefield, the invasion was characterized by extreme brutality, including the mass killing of millions of civilians and the murder of over one million Soviet Jews. Ultimately, the German offensive stalled at the outskirts of Moscow on 5 December 1941, marking a decisive turning point that prevented the total collapse of the Soviet Union.

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