Case Blue

Belligerents

Soviet UnionCommanders and leaders

Adolf Hitler

Franz Halder

Kurt Zeitzler

Fedor von Bock

Maximilian von Weichs

Wolfram von Richthofen

C. Constantinescu-Claps

Gusztáv Jány

Italo Gariboldi

Petre Dumitrescu

Joseph Stalin

Georgy Zhukov

Aleksandr Vasilevsky

Filipp Golikov

Konstantin Rokossovsky

Stepan KrasovskyStrength

Initially: 1,570,287–1,805,000 (incl.Italian Eighth Army from early August)

: 1,210,861
: 235,000 Italian Eighth Army
: 209,000 Hungarian Second Army
: 159,426
1,934 tanks/assault guns
1,593–2,035 aircraft

Initially: 1,715,000
1,000,000 (in reserve)
2,959–3,720 tanks
1,671 aircraft
16,500 artillery pieces
Total:
2,715,000Casualties and losses:
200,000
700 tanks destroyed
:
~150,000
Total: 350,000 (excluding 150,000 casualties in the first phase of the Battle of the Caucasus) 1,200,000
4,862 tanks and SPG destroyed or damaged
(including casualties in the first phase of the Battle of the Caucasus)

Case Blue (German: Fall Blau) was the Wehrmacht's plan for the 1942 summer offensive in southern Russia between 28 June and 24 November 1942, during World War II. The objective was to capture the oil fields of Baku (Azerbaijan SSR), Grozny and Maikop, to enable the Germans to obtain fuel and also to deny it to the Soviet Union, bringing about the complete collapse of the Soviet war effort.

After Operation Barbarossa failed to destroy the Soviet Union as a political and military threat the previous year, Adolf Hitler recognized that Germany was now locked in a war of attrition and he was also aware that Germany had a chronic fuel shortage and would not be able to continue attacking deeper into Soviet territory without more. Hitler ordered the preparation of offensive plans for summer 1942 to secure the Soviet oil fields in the Caucasus. The operation involved a two-pronged attack: one from the Axis right flank against the oil fields of Baku, known as Operation Edelweiss, and one from the left flank to protect the flank of the first attack, moving in the direction of Stalingrad along the Don River, known as Operation Fischreiher.

Army Group South (Heeresgruppe Süd) was divided into Army Group A and Army Group B (Heeresgruppe A and Heeresgruppe B). Army Group A was to fulfil Operation Edelweiss by crossing the Caucasus Mountains to reach the Baku oil fields, while Army Group B protected its flanks along the Volga by fulfilling Operation Fischreiher. Supported by 2,035 Luftwaffe aircraft and 1,934 tanks and assault guns, the 1,570,287-man Army Group South began the offensive on 28 June, advancing 48 kilometers on the first day and easily brushing aside the 1,715,000 Red Army troops opposite, who wrongly expected a German offensive on Moscow even after Blau commenced. The Soviet collapse in the south allowed the Germans to capture the western part of Voronezh on 6 July and reach and cross the Don River near Stalingrad on 26 July. Army Group B's approach toward Stalingrad slowed in late July and early August owing to constant counterattacks by new Red Army reserves and overstretched German supply lines. The Germans defeated the Soviets in the Battle of Kalach and the Battle of Stalingrad began in late August. Non-stop Luftwaffe bombing, artillery-fire and street fighting destroyed the city and inflicted many casualties on the Red Army. After three months of battle, the Germans controlled 90 percent of Stalingrad on 19 November.

In the south, Army Group A captured Rostov-on-Don on 23 July and swept south from the Don to the Caucasus, capturing the demolished oilfields at Maikop on 9 August and Elista on 13 August near the Caspian Sea coast. Determined Soviet resistance and the long distances from Axis sources of supply reduced the Axis offensive to local advances only and prevented the Germans from completing their strategic objective of capturing the main Caucasian oilfield at Baku. Luftwaffe bombers destroyed the oilfields at Grozny but attacks on Baku were prevented by the short range of the German fighters.

The Red Army defeated the Germans at Stalingrad, following Operation Uranus and Operation Little Saturn. This defeat forced the Axis to retreat from the Caucasus during the Battle of Caucasus to avoid being cut off by the Red Army, that was now advancing from Stalingrad towards Rostov. Only the Kuban region remained tentatively occupied by Axis troops.