Case Blue (Fall Blau)

Background

After Operation Barbarossa stalled before Moscow in the winter of 1941, Germany faced a critical fuel shortage. By late 1941, Romania warned Hitler that its oil reserves were exhausted and current production could not meet German demands. At a conference at Army Group South headquarters on 1 June 1942, Hitler declared: "If I do not get the oil of Maikop and Grozny, then I must end this war."

The Plan

Führer Directive No. 41 (5 April 1942) laid out a three-stage offensive:

• Blau I: Second Army and Fourth Panzer Army (Hermann Hoth) would attack from Kursk toward Voronezh, anchoring the northern flank.
• Blau II: Sixth Army (Friedrich Paulus) would advance from Kharkov to the Volga at Stalingrad. The city's capture was not deemed essential; the directive stated it was enough to bring it under artillery fire to neutralize it as an industrial and communications centre.
• Blau III: First Panzer Army and Seventeenth Army would break through the lower Don and drive into the Caucasus.

Execution and the Fateful Split

The offensive opened on 28 June 1942 with sweeping initial success. Soviet forces, concentrated around Moscow, collapsed in the south. But on 9 July, Hitler altered the plan, ordering the simultaneous capture of Stalingrad and the Caucasus. He split Army Group South into Army Group A (Wilhelm List, toward the Caucasus) and Army Group B (Fedor von Bock, toward Stalingrad). The division overstretched supply lines and opened a gap between the two forces.

Army Group A captured Maikop on 9 August, but Soviet sabotage had rendered the oilfields nearly useless. Army Group B's advance bogged down in the street-by-street attrition of Stalingrad from late August. On 19 November 1942, the Soviet Operation Uranus encircled the Sixth Army, turning Case Blue into a decisive German defeat and the turning point of the Eastern Front.

Assessment

Military historians identify Hitler's dispersal of objectives, particularly his growing obsession with Stalingrad at the expense of the original economic goal of the oilfields, as the core operational failure of Case Blue. Stalingrad was conceived as flank cover, not a primary target; Hitler's intervention transformed a secondary task into the campaign's fatal center of gravity.