Case Blue

Case Blue was Germany’s second and last great strategic offensive on the Eastern Front – the last after which the Wehrmacht could still hope to win the war against the Soviet Union. It opened on 28 June 1942 with a thrust from the Kursk area towards Voronezh, and within five months it had carried the German army and its allies further east than ever before: to the Volga at Stalingrad, to the summit of Mount Elbrus and to the Terek, a few dozen kilometres from the oilfields of Grozny. The objective set by Adolf Hitler was the oil of the Caucasus, and, along the way, the destruction of the Soviet forces in the south. Neither was achieved. The Red Army, having learnt from the defeats of 1941 and the spring of 1942, for the most part withdrew before the pincers could close, and then stood fast in the ruins of Stalingrad and in the passes of the Caucasus. When the offensive bogged down in the autumn, the German forces were stretched along a front twice as long as in June, and its weakest sectors on the Don were held by Romanian, Hungarian and Italian armies.

Name and dates

The code name “Blau” (Blue) was given to the summer offensive at the beginning of April 1942, when Hitler signed Directive No. 41. Before that the Army High Command had called it “Siegfried”. After operational documents fell into Soviet hands on 19 June, it was renamed “Braunschweig” on 30 June, and its individual phases were given the code names “Clausewitz” and “Dampfhammer”. Once the forces were divided in July, the drive on the Caucasus was named Operation Edelweiss and the drive on Stalingrad Operation Fischreiher (Heron). Historians, Polish ones included, have nonetheless kept the original name: Case Blue, or Fall Blau. Soviet and Russian historians have no single name for it; they divide the summer and autumn of 1942 into the Voronezh–Voroshilovgrad operation (28 June – 24 July), the defensive phase of the Battle of Stalingrad (from 17 July) and the defensive phase of the Battle of the Caucasus (from 25 July).

The starting date may be taken as 28 June, when the army group of Colonel General Maximilian von Weichs went over to the attack. The earlier preparatory operations – “Wilhelm” near Vovchansk (10–15 June) and “Fridericus II” near Kupiansk (22–25 June) – belong to its prelude. The closing date is 18 November 1942, the last day before the Soviet counter-offensive at Stalingrad that turned the course of the war in the south. The fighting in Stalingrad itself, which began on 23 August, forms the separate Battle of Stalingrad.

Background

Operation Barbarossa had not brought Germany victory in 1941, and the winter counter-offensive before Moscow had forced the Wehrmacht onto the defensive. By the spring of 1942 the armies in the east had lost more than a million men and could no longer attack along the whole front. Hitler, who in December had taken personal command of the Army, decided to seek a decision in the south. Directive No. 41 of 5 April ordered that the Soviet forces west of the Don be destroyed first and the oilfields of the Caucasus seized afterwards. Maikop and Grozny produced about a tenth of Soviet oil, Baku about four-fifths. Germany, cut off by the blockade from oil from overseas and dependent on Romania and on synthetic fuel, needed that oil as urgently as it wanted to deny it to the enemy. The directive named Stalingrad as the point at which the last phase of the operations on the Don was to close. The aim was to “try to reach Stalingrad itself, or at least to bring it under the fire of heavy weapons”, not necessarily to capture it.

In the spring the Germans cleared the ground in front of them. In the Crimea, Colonel General Erich von Manstein’s 11th Army routed the Crimean Front on the Kerch Peninsula in May and on 7 June began the third assault on Sevastopol. Near Kharkiv the Soviet offensive of Marshal Semyon Timoshenko ended in the Second Battle of Kharkov and the Barvenkovo pocket, in which the main forces of three armies were killed or captured. The Southwestern Front and the Southern Front lost the reserves that were to have halted the summer offensive. In June two further operations with limited aims, “Wilhelm” and “Fridericus II”, in which, according to German reports, about 24,800 and 22,800 prisoners respectively were taken, pushed the German front across the Donets and up to Kupiansk, onto the start line for the main offensive.

The Soviet Supreme High Command failed to divine the German intention. Joseph Stalin believed that the Wehrmacht would strike at Moscow again, and he kept most of his reserves there. He was confirmed in this by a German deception operation, Operation Kremlin. On 19 June a light reconnaissance aircraft carrying Major Joachim Reichel, operations officer of the 23rd Panzer Division, came down on the Soviet side of the front near Kharkiv. On him the Russians found the orders for XXXX Panzer Corps for the first phase of the offensive. Stalin took them either for a ruse or for the plan of a merely local attack. Hitler had the corps commander, General Georg Stumme, and his chief of staff court-martialled for breaching the rules of secrecy.

Plan and forces

Directive No. 41 envisaged a series of successive, interlocking blows from north to south. First Weichs’s group – the 2nd Army, Colonel General Hermann Hoth’s 4th Panzer Army and General Gusztáv Jány’s Hungarian 2nd Army – was to advance from the Kursk area to Voronezh. Hoth’s panzer divisions were then to wheel south-east along the Don to meet General Friedrich Paulus’s 6th Army, attacking from eastern Ukraine, and together with it to encircle the Soviet forces between the Donets and the Don. In the third phase these forces were to push down the Don towards Stalingrad and link up there with Colonel General Ewald von Kleist’s 1st Panzer Army and the 17th Army, advancing from the Donets and from the Taganrog area. Only then was the drive into the Caucasus to begin. The whole operation was commanded by Field Marshal Fedor von Bock, commander of Army Group South. As early as April Hitler ordered the headquarters of a second army group to be prepared, which was to take over the southern wing for the march into the Caucasus.

The figures given for both sides vary according to which units are counted. According to the German returns cited by historians, Army Group South committed some 900,000 soldiers and more than 1,200 tanks to the opening blows. Counting all the German and allied armies in the south, including those that arrived at the front during the summer, other calculations give more than one and a half million men. The army group was supported by Luftflotte 4 under Colonel General Alexander Löhr, and from July under Colonel General Wolfram von Richthofen, with more than 1,600 aircraft – almost two-thirds of the German air strength in the east. On the Soviet side, the threatened sector was held by Lieutenant General Filipp Golikov’s Bryansk Front, Timoshenko’s Southwestern Front and Lieutenant General Rodion Malinovsky’s Southern Front. Russian statistical studies put their strength at about 1.3 million men, but the divisions of the Southwestern Front had been bled white at Kharkov, and the strongest reserves of the Stavka stood on the Moscow axis.

Towards Voronezh (28 June – 24 July)

On the morning of 28 June, after air strikes and an artillery bombardment, Weichs’s group struck at the junction of the 13th and 40th Armies of the Bryansk Front. The 24th Panzer Division broke through the defences on the very first day and reached the headquarters of the 40th Army, which fled, abandoning its radio sets. Golikov threw tank corps into a counter-attack, but they went into action one at a time, without communications or air cover, and were destroyed one after another by German anti-tank guns and aircraft. On 30 June Paulus’s 6th Army set off further south; it broke through the front of the 21st and 28th Armies and on 2 July linked up with Hoth’s armoured spearhead east of Stary Oskol. Only a few divisions were caught in the pocket, however: most of the Soviet troops had managed to withdraw.

During the night of 3–4 July German units crossed the Don near Voronezh, and on 6 July they broke into the part of the city lying on the right bank of the Voronezh river. Stalin and the Chief of the General Staff, Colonel General Aleksandr Vasilevsky, appointed on 26 June, still believed that the Germans would turn north from here towards Moscow, and they drew more and more reserves to the city. On 7 July the Voronezh Front was formed from the southern wing of the Bryansk Front and from reserve armies; from 14 July it was commanded by Lieutenant General Nikolai Vatutin. From 6 July the new 5th Tank Army of Major General Aleksandr Lizyukov attacked north-west of the city. After a week of fighting it had been shattered and was disbanded, and its commander was killed on 23 July in a further attack. The fighting in Voronezh went on until 24 July, and the front came to rest in the city itself, where the Russians held the districts on the left bank and bridgeheads on the western bank of the Don.

The battle for Voronezh, however, tied down the German panzer divisions for longer than the plan had allowed. Instead of heading south at once, Hoth’s corps waited to be relieved by the infantry of the 2nd Army. Bock defended the decision to take the city; Hitler considered it a waste of time. Meanwhile the 4th Panzer Army and the 6th Army moved down the Don towards Rossosh, and on 9 July the 1st Panzer Army also went over to the attack from the Donets. The German pincers that were meant to trap Timoshenko’s and Malinovsky’s forces between the Donets and the Don closed mostly on rearguards: the Southwestern and Southern Fronts fell back eastwards, in many places in disorder, but without being encircled. In mid-July one more pocket closed near Millerovo, smaller than those of 1941.

Two army groups and Directive No. 45

On 9 July Army Group South was divided. The southern wing – the 1st Panzer Army, the 17th Army and the Romanian troops on the Sea of Azov – came under the command of Field Marshal Wilhelm List’s Army Group A. The northern wing, with the 2nd Army, the 4th Panzer Army, the 6th Army and the Hungarians, formed Army Group B. The dispute over Voronezh and over the pace of the advance cost Bock his post: on 13 July Hitler decided to dismiss him, and Weichs took over Army Group B. On 16 July Hitler moved to his new Werwolf headquarters near Vinnytsia in order to direct the offensive at close quarters.

From this headquarters came the orders that changed the April plan. In mid-July the 4th Panzer Army was sent south, towards the lower Don, to help Kleist trap the Soviet forces around Rostov. The encirclement failed, and two panzer armies jammed the roads in a single area while the 6th Army advanced on Stalingrad alone, without the armoured support it had originally been promised. On 23 July Hitler signed Directive No. 45, declaring that the aims of the first phase had been “broadly achieved” and that only “weak enemy forces” had managed to escape. Army Group A was now to destroy the Soviet forces beyond the Don, take the whole eastern coast of the Black Sea and then Grozny and Baku. Army Group B was at the same time to capture Stalingrad, block the Volga and advance to Astrakhan. Instead of successive phases of a single operation there were now two offensives in diverging directions, and Army Group A also lost the 11th Army from Sevastopol, which was sent to Leningrad. The Chief of the Army General Staff, General Franz Halder, complained in his diary that Hitler persistently underestimated the enemy, but in July he did not oppose the directive.

Rostov and “Not a step back!”

Malinovsky’s Southern Front was retreating across the Don in ever greater disorder. On 23 July German troops broke into Rostov-on-Don, which the Germans had already taken once in November 1941 and lost a week later. This time the defenders, although the city had been fortified over the winter with three rings of trenches, withdrew to the southern bank and blew up the bridges. The last fighting in the western part of the city died down on 24 and 25 July, and German engineers were throwing pontoon bridges across the Don that same night. By the end of July Army Group A had several bridgeheads beyond the river along a 200-kilometre stretch between the Sea of Azov and Tsimlyanskaya.

The fall of Rostov and Novocherkassk without a long fight came as a shock to the Soviet leadership. On 28 July Stalin, as People’s Commissar of Defence, signed Order No. 227, known by its words “Not a step back!”. The order, read out to the troops but not published in the press, admitted that the country had lost Ukraine, Belarus and the Baltic region, and with them millions of people and a large part of its grain and industry, and that further retreat would mean ruin. It forbade withdrawal without orders from above, created penal companies and battalions for soldiers and officers guilty of cowardice or indiscipline, and, behind unreliable divisions, blocking detachments which were to shoot those who fled. The Southern Front was disbanded on the same day and its troops were absorbed into Marshal Semyon Budyonny’s North Caucasus Front. Historians assess the effects of the order in different ways: it tightened discipline, but the main reasons why the Red Army stopped retreating in the autumn were fresh reserves, better command and German supply difficulties.

Into the Caucasus (July – November)

Beyond the Don, the steppe of the Kuban and the Stavropol region opened up before Army Group A, and the shattered Soviet armies could not hold it. Kleist’s 1st Panzer Army drove south-east, while Colonel General Richard Ruoff’s 17th Army, with the Romanian 3rd Army, headed south towards Krasnodar. On 29 July the Germans cut the last direct railway linking the heart of the country with the Caucasus. Stavropol fell on 5 August; on 9 August Kleist’s tanks entered Maikop after a march of more than 400 kilometres in under two weeks; and on 12 August the 17th Army took Krasnodar. The Maikop oilfields, however, had been so thoroughly wrecked by the retreating Russians that German technical units were unable to restore production on any significant scale. On 21 August a detachment of men from the 1st and 4th Mountain Divisions planted the German war flag on the summit of Elbrus, the highest mountain of the Caucasus. Hitler greeted this feat with fury, regarding it as a waste of effort on an objective of no military value.

Then the advance began to bog down. Fuel reached the spearheads by rail through Rostov or by air, sometimes even on camels, and panzer divisions stood idle for days at a time without petrol. The air force was increasingly shifted to Stalingrad, while the Soviet defence, organised by General of the Army Ivan Tyulenev’s Transcaucasian Front and the North Caucasus Front, was anchored on mountains and rivers. On 25 August the 1st Panzer Army took Mozdok and on 2 September crossed the Terek, but it came to a halt short of Grozny, at Malgobek. The mountain troops failed to break through the passes of the Main Caucasus Range towards Sukhumi. On the coast the 17th Army had captured most of Novorossiysk by 10–11 September, but the eastern suburbs and the exit from the bay remained in the hands of the 47th Army, and from 25 September the drive on Tuapse – the port through which the coastal road ran – stalled in wooded mountains a few dozen kilometres short of its objective.

Hitler blamed his commanders for the slow pace. After a bitter quarrel on 9 September he demanded List’s resignation and himself took command of Army Group A from his headquarters at Vinnytsia. Halder, who had defended List, was replaced on 24 September by General Kurt Zeitzler. In October the Luftwaffe bombed the refineries at Grozny, but it never reached Baku. Kleist’s last attack, at the end of October, took Nalchik and at the beginning of November reached Gizel, a few kilometres from Ordzhonikidze, today’s Vladikavkaz. A Soviet counter-attack on 6 November almost encircled the 13th Panzer Division there, and it withdrew only with difficulty. This was the furthest point of the German advance into the Caucasus.

In the great bend of the Don

On the Stalingrad axis, on 12 July the Stavka formed the Stalingrad Front, headed first by Timoshenko and from 23 July by Lieutenant General Vasily Gordov. The 62nd and 64th Armies were moved up from the reserve to the Don. From 17 July their forward detachments fought the spearheads of the 6th Army on the river Chir, and Russian historiography regards this day as the start of the Battle of Stalingrad. Paulus, who after the departure of the 4th Panzer Army to the south had few tanks and even less fuel, advanced slowly. At the end of July his panzer corps reached the Don north and south of Kalach, where the Soviet 1st and 4th Tank Armies, thrown together in haste, counter-attacked at great cost. On 31 July Hitler turned Hoth’s 4th Panzer Army back from the lower Don towards Stalingrad, this time from the south, via Kotelnikovo.

On 7 and 8 August the pincers of the 6th Army closed west of Kalach. By 11 August the main forces of the 62nd Army and part of the 1st Tank Army had been destroyed in the pocket, although once again some of the Soviet troops broke through to the eastern bank. On 21 August Paulus’s infantry crossed the Don at Vertyachy and Peskovatka, and on 23 August General Gustav von Wietersheim’s XIV Panzer Corps crossed the steppe between the Don and the Volga in a single day and reached the Volga in the northern suburbs of Stalingrad. On the same day Luftflotte 4 razed a large part of the city to the ground. The number of civilians killed in the air raids of 23 August and the days that followed is disputed: estimates range from several thousand to several tens of thousands. Stalin long refused to allow the population to be evacuated, and only some of the inhabitants were taken across the Volga.

Stalingrad (in brief)

For the defence of the city the Stavka divided its forces into the Stalingrad Front and the Southeastern Front, both coordinated by Colonel General Andrei Yeremenko. On 26 August General of the Army Georgy Zhukov was made Deputy Supreme Commander and sent to the Volga. The attacks he organised from the north, from the corridor between the Don and the Volga, did not cut through the German wedge, but they drew off part of Paulus’s forces. At the end of August the 4th Panzer Army broke through from the south, and on 3 September it linked up with the 6th Army west of the city. The 62nd Army, commanded from 12 September by Lieutenant General Vasily Chuikov, was pinned against the Volga.

The first assault on the city began on 13 September. The fighting raged over the Mamayev Kurgan, the railway station, the grain elevator and the river crossings. In October the 6th Army took most of the factory districts: the Tractor Factory, the Barrikady and the Red October. Chuikov ordered his men to keep as close to the Germans as possible, so that German aircraft and artillery could not strike without endangering their own troops. The last great assault, launched on 11 November, squeezed the defenders into a few narrow bridgeheads along the river. By mid-November the Germans controlled about 90 per cent of the ruins, but the 62nd Army, supplied by night across the Volga, was still holding out. Almost all the forces that Army Group B had available for the offensive went into Stalingrad, and its flanks were stripped bare.

Allies on the Don

In accordance with Directive No. 41, the long northern flank of the offensive, growing ever longer as the advance moved east, was taken over by Germany’s allies. South of Voronezh, on the sector won in July, stood the Hungarian 2nd Army, some 200,000 soldiers sent by Admiral Miklós Horthy. Beyond them, from August, the Italian 8th Army of General Italo Gariboldi took up positions on the middle Don; at Benito Mussolini’s wish it had been expanded from an expeditionary corps to some 230,000 men. Between September and October General Petre Dumitrescu’s Romanian 3rd Army moved onto the Don north-west of Stalingrad, opposite Serafimovich and Kletskaya, while the Romanian 4th Army deployed south of the city. Marshal Ion Antonescu had committed most of the Romanian army in the east.

The allied armies had few anti-tank weapons and few tanks, and the German 22nd Panzer Division, the reserve standing behind the Romanians, was weak and poorly supplied. As early as August Soviet counter-attacks near Serafimovich and on the middle Don pushed back the Italians and left the Red Army with bridgeheads on the right bank of the river. The Germans were unable to eliminate them. It was from here that the main Soviet blow was to come in November.

Losses

The exact losses of the operation as a whole cannot be given, because neither side counted them according to the German definition of “Blau”. According to the Russian statistical study edited by Grigori Krivosheev, in the Voronezh–Voroshilovgrad operation (28 June – 24 July) the Red Army lost 568,000 men, more than 370,000 of them killed, missing or taken prisoner, together with about 2,400 tanks and 780 aircraft. The defensive phase of the Battle of Stalingrad (17 July – 18 November) cost it, according to the same source, about 644,000 men, 324,000 of them irrecoverable losses, and the defensive phase of the Battle of the Caucasus (from 25 July to the end of the year) about 374,000, more than 190,000 of them irrecoverable. German losses were markedly lower, but they grew month by month: according to figures of the German Army High Command, Army Groups A and B alone lost about 70,000 killed, wounded and missing in July. From September the street fighting in Stalingrad cost them the most blood. The losses of the Romanian, Hungarian and Italian armies in this period are not precisely known.

Significance

Case Blue brought Germany its greatest territorial gains of the entire war in the east. The Wehrmacht occupied the Donets Basin, the Kuban, the Stavropol region and part of the North Caucasus, cut the railway from the Caucasus through Rostov and stood on the Volga, the most important route by which oil from Baku flowed to the heart of the country. From then on the Baku refineries had to send their fuel by a roundabout route across the Caspian Sea and Central Asia, and surpluses piled up in storage tanks. Yet Hitler did not get what he had reached for. He did not capture a single major oilfield in a usable state, he did not trap Soviet armies in pockets as in 1941, and every time he changed the plan he took forces away from one thrust to strengthen another. Directive No. 45, which instead of successive phases ordered simultaneous advances on the Caucasus and on Stalingrad, is regarded as one of the gravest command errors of the war, although some historians point out that the April plan already exceeded the available means of supply and demanded more of the allied armies than they could give.

On the Soviet side, the summer of 1942 was the last great retreat of the war. The Red Army lost hundreds of thousands of men and vast territories, but this time its command more often pulled troops back before they could be surrounded, and industry relocated to the Urals produced more tanks, guns and aircraft in 1942 than Germany did. As the German offensive stalled in the ruins of Stalingrad and on the approaches to Grozny and Tuapse, Zhukov and Vasilevsky worked from September on a plan for a counter-offensive, which Stalin approved in November. On 19 November 1942 the Southwestern and Don Fronts struck from their bridgeheads on the Don at the Romanian 3rd Army, and on the following day the Stalingrad Front fell on the Romanian 4th Army. On 23 November the pincers closed near Kalach, trapping Paulus’s 6th Army and part of the 4th Panzer Army in the pocket. At the turn of the year Army Group A had to withdraw from the Caucasus to avoid being cut off. The offensive that was meant to secure the Reich oil for a long war ended in a defeat after which the strategic initiative on the Eastern Front began to pass to the Red Army.