June 1941 - Barbarossa

German invasion of the Soviet Union that opened World War II on the Eastern Front, commencing the largest, most bitterly contested, and bloodiest campaign of the war. Adolf Hitler’s objective for Operation BARBAROSSA was simple: he sought to crush the Soviet Union in one swift blow. With the USSR defeated and its vast resources at his disposal, surely Britain would have to sue for peace. So confident was he of victory that he made no effort to coordinate the invasion with his Japanese ally. Hitler predicted a quick victory in a campaign of, at most, three months.

German success hinged on the speed of advance of 154 German and satellite divisions deployed in three army groups: Army Group North in East Prussia, under Field Marshal Wilhelm von Leeb; Army Group Center in northern Poland, commanded by Field Marshal Fedor von Bock; and Army Group South in southern Poland and Romania under Field Marshal Karl Gerd von Rundstedt. Army Group North consisted of 3 panzer, 3 motorized, and 24 infantry divisions supported by the Luftflotte 1 and joined by Finnish forces. Farther north, German General Nikolaus von Falkenhorst’s Norway Army would carry out an offensive against Murmansk in order to sever its supply route to Leningrad. Within Army Group Center were 9 panzer, 7 motorized, and 34 infantry divisions, with the Luftflotte 2 in support. Marshal von Rundstedt’s Army Group South consisted of 5 panzer, 3 motorized, and 35 infantry divisions, along with 3 Italian divisions, 2 Romanian armies, and Hungarian and Slovak units. Luftflotte 4 provided air support.

Meeting this onslaught were 170 Soviet divisions organized into three “strategic axes” (commanding multiple fronts, the equivalent of army groups)—Northern, Central, and Southern or Ukrainian—that would come to be commanded by Marshals Kliment E. Voroshilov, Semen K. Timoshenko, and Semen M. Budenny, respectively. Voroshilov’s fronts were responsible for the defense of Leningrad, Karelia, and the recently acquired Baltic states. Timoshenko’s fronts protected the approaches to Smolensk and Moscow. And those of Budenny guarded the Ukraine. For the most part, these forces were largely unmechanized and were arrayed in three linear defensive echelons, the first as far as 30 miles from the border and the last as much as 180 miles back.