Case Blue Case Blue ( ) , later renamed Operation Braunschweig , was the German Armed Forces ' ( " Wehrmacht " ) name for its plan for the 1942 strategic summer offensive in southern Russia between 28 June and 24 November 1942 . The operation was a continuation of the previous year ' s Operation Barbarossa intended to finally knock the Soviet Union out of the war , and involved a two - pronged attack against the rich oilfields of Baku as well as an advance in the direction of Stalingrad along the Volga River , to cover the flanks of the advance towards Baku . For this part of the operation , Army Group South ( " Heeresgruppe Süd " ) of the German Army ( " Wehrmacht Heer " ) was divided into Army Groups A and B ( " Heeresgruppe A " and " B " ) . Army Group A was tasked with crossing the Caucasus mountains to reach the Baku oil fields , while Army Group B protected its flanks along the Volga . Initially , the German offensive saw spectacular gains with a rapid advance into the Caucasus capturing vast areas of land and several oil fields . However , the Red Army decisively defeated the Germans at Stalingrad , following Operations Uranus and Little Saturn . This defeat forced the Axis to retreat from the Caucasus in fear of becoming trapped . Only the city of Kursk and the Kuban region remained tentatively occupied by Axis troops . Axis strategy . Background . On 22 June 1941 the Germans began Operation Barbarossa with the intention of defeating the Soviets in a Blitzkrieg lasting only months . The offensive met with initial success and the Red Army suffered some major defeats , before the Germans were stopped at Moscow . Although the Germans captured vast areas of land and important industrial centers , the Soviet Union remained in the war . In the winter of 1941 / 1942 the Soviets struck back in a series of counteroffensives , repelling the German threat to Moscow , and making it clear the campaign against the Soviets would become a long battle of attrition . Despite these setbacks , Hitler wanted an offensive solution , for which he required the rich oil resources of the Caucasus . By February 1942 , the Army High Command ( OKH ) had begun to develop plans for a follow - up campaign to the failed Barbarossa offensive with the Caucasus as its principal objective . On 5 April 1942 , Hitler laid out the key elements of the plan now known as " Case Blue " ( " Fall Blau " ) in " Führer " Directive No . 41 . The directive stated the main goals of the summer campaign on the Eastern Front - holding attacks for AG Centre , the capture of Leningrad and link up with Finland for AG North and the capture of the Caucasus Region for Army Group South . The oilfields . The immense Caucasus region , traversed by its eponymous mountains , is bounded by the Black Sea to the west and the Caspian Sea to the east . The region north of the mountains was a production center for grain , cotton and heavy farm machinery while its two main oilfields , at Maykop , near the Black Sea , and Grozny , adjoining the Caspian , produced about 10 percent of all Soviet oil . South of the mountains lay the densely populated region of Transcaucasia , comprising Georgia , Azerbaijan and Armenia . This heavily industrialised area , which had a greater population density than New York State , contained some of the largest oilfields in the world . Baku , the capital of Azerbaijan , was one of the richest , producing 80 per cent of the Soviet Union ' s oil – about 24 million tons in 1942 alone . The Caucasus also possessed plentiful coal and peat , as well as nonferrous and rare metals . Manganese deposits at Chiaturi , in Transcaucasia formed the richest single source in the world , yielding 1 . 5 million tons of manganese ore annually , half of the Soviet Union ' s total production . The Kuban region of the Caucasus also contained vast swaths of wheat , corn , sunflower seeds and sugar beets , all essential in the production of food . These resources were of immense importance to Hitler and the German war effort . Of the three million tons of oil Germany consumed per year , 85 per cent was imported - mainly from the United States , Venezuela and Iran . When war broke out in September 1939 , the British naval blockade cut Germany off from the Americas and the Middle East leaving the country reliant on oil - rich European countries such as Romania to supply the resource . An indication of German reliance on Romania is evident from its oil consumption ; in 1938 , just one - third of the 7 , 500 , 000 tons consumed by Germany came from domestic stocks . Oil had always been Germany ' s Achilles heel , and by the end of 1941 , Hitler had nearly exhausted Germany ' s reserves , which left him with only two significant sources of oil , the country ' s own synthetic production and the Romanian oilfields , with the latter supplying 75 % of Germany ' s oil imports in 1941 . Aware of his declining oil resources and fearful of enemy air attacks on Romania — Germany ' s only source of crude oil — Hitler ' s strategy was increasingly driven by the need to protect Romania and acquire new resources , essential if he wanted to continue waging a prolonged war against a growing list of enemies . In late 1941 , the Romanians warned Hitler that their stocks were exhausted and they were unable to meet German demands . For these reasons , the Soviet oilfields were extremely important to Germany ' s industry and armed forces as the war became global , the power of the Allies grew , and shortages started to occur in Axis resources . Planning . Axis forces . The offensive was to be conducted across the southern Russian ( Kuban ) steppe utilizing the following Army Group units : German air strength in the east numbered 2 , 644 aircraft on 20 June 1942 , over 20 % more than a month earlier . Whereas in 1941 most units fought on the central front supporting Army Group Centre , 1 , 610 aircraft ( 61 % ) , supported Army Group South . Initially commanded by Löhr , on 20 July 1942 , Wolfram Freiherr von Richthofen took command of " Luftflotte 4 " . The German plan involved a three - staged attack : The strategic objectives of the operation were the oilfields at Maykop , Grozny and Baku . As in Barbarossa , these movements were expected to result in a series of grand encirclements of Soviet troops . Soviet forces . The Soviet army command ( " Stavka " ) failed to discern the direction of the main German strategic offensive anticipated in 1942 , even though they were in possession of the German plans . On 19 June , the chief of operations of the 23rd Panzer Division , Major Joachim Reichel , was shot down over Soviet - held territory while flying an observation aircraft over the front near Kharkiv . The Soviets recovered maps from his aircraft detailing the exact German plans for Case Blue . The plans were handed over to " Stavka " , in Moscow . Joseph Stalin , however , believed it to be a German ruse , remaining convinced that the primary German strategic goal in 1942 would be Moscow , in part due to Operation Kremlin ( " Fall Kreml " ) , a German deception plan aimed at the city . As a result , the majority of Red Army troops were deployed there , although the direction from which the Case Blue offensive would come was still defended by the Bryansk , Southwestern , Southern and North Caucasian Front s . With about 1 million soldiers at the frontline and another 1 . 7 million in reserve armies , their forces accounted for about one quarter of all Soviet troops . Following the disastrous start of Case Blue for the Soviets , they reorganised their frontlines several times . Over the course of the campaign , the Soviets also fielded the Voronezh Front , Don Front , Stalingrad Front , Transcaucasian Front , and the Caucasian Front , though not all existed at the same time . With the German thrust expected in the north , " Stavka " planned several local offensives in the south to weaken the Germans . The most important of these was aimed at the city of Kharkiv and would be conducted mainly by the Southwestern Front under Semyon Timoshenko , supported by the Southern Front commanded by Rodion Malinovsky . The operation was scheduled for 12 May , just prior to a planned German offensive in the area , which would prove disastrous for the operation . The ensuing Second Battle of Kharkov ended in disaster and severely weakened the Soviets . At the same time , the Axis clearing of the Kerch Peninsula together with the Battle of Sevastopol , which lasted until July , weakened the Soviets further and allowed the Germans to supply Army Group A across the Kerch Peninsula through the Kuban . The offensive . Opening phase . The German offensive commenced on 28 June 1942 , with Fourth Panzer Army starting its drive towards Voronezh . Due to a chaotic Soviet retreat , the Germans were able to advance rapidly , restoring " Wehrmacht ' s " confidence for the upcoming major offensive . Close air support from the Luftwaffe also played an important role in this early success . It contained the Red Air Force , through air superiority operations , and interdiction through attacks on airfields and Soviet defence lines . At times the German air arm acted as a spearhead rather than a support force , ranging on ahead of the tanks and infantry to disrupt and destroy defensive positions . As many as 100 German aircraft were concentrated on a single Soviet division in the path of the spearhead during this phase . General Kazakov , the Bryansk Front ' s chief of staff , noted the strength and effectiveness of Axis aviation . Within 26 days , the Soviets lost 783 aircraft from the 2nd , 4th , 5th and 8th Air Armies , compared to a German total of 175 . By 5 July , forward elements of Fourth Panzer Army had reached the Don River near Voronezh and became embroiled in the battle to capture the city . Stalin and the Soviet command still expected the main German thrust in the north against Moscow , and believed the Germans would turn north after Voronezh to threaten the capital . As a result , the Soviets rushed reinforcements into the town , to hold it at all costs and counterattacked the Germans ' northern flank in an effort to cut off the German spearheads . Pavel Rotmistrov ' s 5th Tank Army managed to achieve some minor successes when it began its attack on 6 July , but was forced back to its starting positions by 15 July , losing about half of its tanks in the process . Although the battle was a success , Hitler and von Bock , commander of Army Group South , argued over the next steps in the operation . The heated debate , and continuing Soviet counterattacks , which tied down Fourth Panzer Army until 13 July , caused Hitler to lose his temper and dismiss von Bock . As part of the second phase of the operation , on 9 July , Army Group South was split into Army Group A and B with Wilhelm List appointed as commander of Army Group A in place of von Bock . Only two weeks into the operation , on 11 July , the Germans began to suffer logistics difficulties , which slowed down the tempo of the advance . The German Sixth Army was continually delayed by fuel shortages . Eight days later , on 20 July , shortages of fuel were still undermining operations , leaving many units unable to execute their orders . The 23rd Panzer Division and 24th Panzer Division both became stranded during the opening phase . Once again , as it had done during the Norwegian Campaign in April 1940 , and " Barbarossa " in 1941 , the Luftwaffe ' s Junkers Ju 52 transport fleet flew in supplies to keep the army going . The situation remained difficult with German troops forced to recover fuel from damaged or abandoned vehicles , and in some cases , leave behind tanks and vehicles with heavy fuel consumption to continue their advance . This undermined the strength of the units , which were forced to leave fighting vehicles behind . Nevertheless , the Luftwaffe flew in 200 tons of fuel per day to keep the army supplied . Despite this impressive performance in keeping the army mobile , Löhr was replaced by the more impetuous and offensive - minded von Richthofen . Splitting of Army Group South . Believing that the main Russian threat had been eliminated , desperately short of oil and needing to meet all the ambitious objectives of Case Blue , Hitler made a series of changes to the plan in " Führer " Directive No . 45 : There is no evidence Hitler was opposed by , or received complaints from Franz Halder , the Chief of the General Staff , or anyone else , about the directive until August 1942 . The new directive created enormous logistical difficulties with Hitler expecting both Army Groups to advance along different logistics routes . Logistics lines were already at breaking point with ammunition and fuel shortages most apparent , and it would be impossible to advance using the present conservative supply rates he demanded . The divergence of the two Army Groups would also open a dangerous gap between the armies , which could be exploited by the enemy . Moreover , no effective deployment of tactical resources was made in light of the task at hand . Inexplicably the Italian Alpine Corps , of the Italian Army in Russia , did not arrive in the Caucasus Mountains with Army Group A , instead remaining with Paulus ' Sixth Army . Army Group A was therefore expected to operate in mountain terrain with only three mountain divisions and two infantry divisions unsuited to the task . The splitting of Army Group South enabled the launching of Operation Edelweiss and Operation Fischreiher , the two main thrusts of the army groups . Both groups now had to strive for their goals simultaneously , instead of achieving them consecutively on a phased basis . The success of Sixth Army ' s initial advance was such that Hitler ordered Fourth Panzer Army south to assist First Panzer Army in forcing a crossing of the lower Don River . Army Group A action — Caucasus campaign . Breaking into the Caucasus . With heavy air support from the Ju 87s of " Sturzkampfgeschwader 77 " , List ' s Army Group A recaptured Rostov , the " gate to the Caucasus " , on 23 July 1942 without much resistance . The " Luftwaffe " was in complete control of the skies in the early phase of the operation thus easing the task of the ground forces . With the Don River crossing secured and Sixth Army ' s advance flagging on the Volga front , Hitler sent Fourth Panzer Army back to the Volga line , reassigning it to Army Group B . In doing so , the Germans wasted enormous amounts of precious fuel transferring the units by air and land to the Volga front . After crossing the Don River on 25 July , Army Group A fanned out on a broad front from the Sea of Azov to Zymlianskaya . The German Seventeenth Army , along with elements of the Eleventh Army and the support of the Romanian Third Army , now manoeuvred west towards the Black Sea ' s eastern coast , while First Panzer Army attacked southeast . While Seventeenth Army could only advance steadily , First Panzer Army roamed at will through the Soviet lines . On 29 July the Germans cut the last direct railroad between central Russia and the Caucasus region , causing considerable panic among the Soviet High Command and Stalin , which was illustrated by the passing of the famous Order No . 227 - " Not a step back ! " . Salsk was captured on 31 July and Stavropol on 5 August . Although the Army Group made rapid ground during its advance , by 3 August its vanguard comprised only light mobile forces with most of the tanks lagging behind due to lack of fuel and logistical breakdowns . Despite the best efforts of Kurt Pflugbeil ' s " Fliegerkorps IV " , which flew in supplies around the clock , the problem did not abate . On 9 August , First Panzer Army reached Maikop at the foothills of the Caucasus range , having advanced more than in less than two weeks . The western oil fields near Maikop were seized in a commando operation on 8 – 9 August . Shortly afterwards Pyatigorsk was taken . On 12 August , Krasnodar was captured and German mountain troops hoisted the Nazi flag on the highest mountain of the Caucasus , Mount Elbrus . The German advance had been highly successful , but long lines of supply hindered the continued advance . Of primary deficiency was a lack of petrol . As the Black Sea was not considered safe for transit , fuel had to be brought by rail through Rostov , or flown in . The armoured divisions were sometimes at a standstill for weeks . Even the petrol trucks were without supplies , and oil had to be brought up on camels . With the Soviets often retreating instead of fighting , the number of captured Soviet troops fell short of expectations — only 83 , 000 in all . At the same time , the focus of the German command shifted to the struggle at Stalingrad . The High Command began pulling some of Kleist ' s mobile forces to assist in the battle . In addition , Kleist was required to give up the whole of his flak corps and most of his Luftwaffe support , with only reconnaissance aircraft being left behind . At the same time , the Soviets brought in a bomber force of about 800 aircraft , a third of which were operational . Lacking aircover and flak units , the Soviet bombers were able to harass and slow the German advance . The quality of the Soviet resistance increased as well , with many of the forces used coming from local levies . To Kleist ' s point of view , they fought with greater determination for their home territory . The number of replacements and supplies the Soviets committed increased as well . Faced with these difficulties , the Axis advance slowed from 28 August onwards . Battle for the oilfields . Meanwhile in the southeast , the " Wehrmacht " headed in the direction of Grozny and Baku , the other important petroleum centres . More installations and industrial centres fell into German hands , many intact or only slightly damaged during the Russian retreat from the area . In August – September the Taman Peninsula and a part of the Novorossisk naval base were taken . Thereafter , the Germans continued their advance toward Tuapse along the Black Sea coast . In the east , Elista was taken on 13 August . Further south , the German advance stalled north of Grozny , after taking the town of Mozdok on 25 August . German paratroopers assisted a raging insurgency in Chechnya , operating behind the Soviet lines . However , the mountain troops failed to secure the Black Sea ports , and the advance fell short of Grozny as logistical issues arose once more . The Soviets , determined to defend the oil fields there , dug in the 9th and 44th Armies of the North Transcaucasian Front along the rocky Terek River bank in front ( north ) of the city . The " Luftwaffe " was unable to support the German land forces that deep within enemy territory , allowing Soviet aviation to attack Axis - held bridges and logistics virtually unopposed . The Germans crossed the river on 2 September , but progress was extremely slow . In an attempt to improve the logistics situation , Axis naval vessels transported 30 , 605 men , 13 , 254 horses , and 6 , 265 motor vehicles across the Black Sea to the Caucasus from Romanian ports , between 1 – 2 September . Thus reinforced , the Germans captured most of the Black Sea naval bases , but stalled at Novorossisk , where the Soviet 47th Army dug in and prepared for a long siege . Novorossisk fell on 10 September 1942 , after a bitter four - day battle . This was List ' s final victory in the Caucasus , and an incomplete one – the Soviet 47th Army still held the heights south of the port , and several strategically important coastal roads . Several attempts to push out of Novorossisk were repulsed with heavy losses . The Axis also proved unable to overcome coastal plain defences between Novorossisk and Tuapse , and had only the strength to stabilise the line . Romanian Army losses were particularly high with the Romanian 3rd Mountain Division nearly wiped out by a Soviet counter - attack on 25 – 26 September . Meanwhile , further east , the Axis enjoyed greater success . On 1 September , the Germans took ( ) , halfway between Elista and Astrakhan . During August and September , German patrols harassed and interrupted the railway between Kizlyar , northeast of Grozny , and Astrakhan , marking the farthest advance of the German forces towards the Caspian Sea . In the south , the First Panzer Army ' s advance on Grozny stalled after meeting heavy resistance on the ground from Soviet forces supported by the 14th Air Army , which blunted their attacks . By late September and into early October , logistics breakdowns and heavy resistance meant the Axis were barely moving . Local attacks still proved successful . On 26 or 28 October 1942 , the 2nd Romanian Mountain Division and 13th Panzer Division took Nalchik , capital of Kabardino - Balkaria , then captured 10 , 000 Soviets in two days , before the Axis advance toward Grozny stalled again west of the city at the town of Vladikavkaz . On 5 November , Alagir was seized and the Alagir - Beslan - Malgobek line would then mark the farthest German advance in the south . By this time , the gap between Army Group A and B had dangerously exposed them to a counter strike . Only the German 16th Motorized Infantry Division remained inside the gap , defending the left flank of the First Panzer Army by securing the road towards Astrakhan . In November , after several unsuccessful Soviet counterattacks , the Germans decided to remain on the defensive , waiting for the spring of 1943 to resume the offensive if the Stalingrad operations proved successful . Luftwaffe offensive against the oil fields . In the first week of October 1942 , Hitler came to recognise that the capture of the Caucasus oil fields was unlikely before the Russian Winter forced the German forces to take up winter positions . Unable to capture them , he was determined to deny them to the enemy and ordered the " Oberkommando der Luftwaffe " ( OKL ) to inflict as much damage as possible . On 8 October , Hitler called for the air offensive to be carried out no later than 14 October , as he required air assets for a major effort at Stalingrad . As a result , on 10 October 1942 , " Luftflotte " 4 ' s " Fliegerkorps IV " was ordered to send every available bomber against the oilfields at Grozny . The air fleet was in poor shape by this time – Von Richthofen had begun Case Blue with 323 serviceable bombers out of a total of 480 . He was now down to 232 , of which only 129 were combat ready . Nevertheless , the force could still deliver damaging blows . Attacks on the refineries reminded von Richthofen of the attacks on Sevastopol several months earlier . Thick black smoke rose from the refineries to a height . On 12 October further raids caused even more destruction . It had been a strategic mistake not to have made greater efforts to hit the oil refineries at Grozny and Baku sooner as their destruction would have been a greater blow to the Soviets than the loss of Stalingrad , where most of the air fleet was deployed . On 19 November , the Soviet counter - offensive at Stalingrad compelled von Richthofen to once more withdraw his units north to the Volga and bring an end to the aerial offensive . Much damage was done at Grozny , but the remaining oilfields were beyond the logistical reach of the German Army as well as the fighter aircraft of the Luftwaffe . Grozny was within range of German bombers from " Fliegerkorps IV " , based near the Terek river . But Grozny and the captured oilfields at Maykop produced only ten per cent of Soviet oil . The main fields at Baku were out of German fighter range . German bombers could have reached them , but it meant flying the most direct , thus most predictable route without protection . In August it may have been possible to carry out these operations owing to the weakness of Soviet air power in the region , but by October it had been considerably strengthened . Army Group B action — the Volga campaign . Clearing the Don Bend . On 23 July the main body of Army Group B started its advance toward the Don River . The Germans now met with increasing Soviet resistance from the newly formed Stalingrad Front , made up of the 62nd and 64th Soviet Armies . On 26 July , XIV Panzer Corps broke through the Soviet lines and reached the Don River . The recently formed First and Fourth Tank Armies conducted several counterattacks against Sixth Army ' s advance , threatening XIV Panzer Corps , but neither attack by the inexperienced troops proved successful . In the south , Fourth Panzer Army made better progress against the Soviet 51st Army . After Hoth ' s Panzers crossed the Don , they started to advance on Kotelnikovo , reaching the town by 2 August . Heavy Soviet resistance convinced Paulus that the Sixth Army was not strong enough to cross the Don by itself , so he waited for Fourth Panzer Army to fight its way north . On 4 August , the Germans were still from Stalingrad . By 10 August , the Red Army had largely been cleared from the western bank of the Don River but Soviet resistance continued in some areas , further delaying Army Group B ' s eastward offensive . Furthermore the " Wehrmacht " could not make appreciable headway towards Stalingrad because of heavy logistical problems caused by the poor state of Soviet roads , which created bottlenecks and shortages of both munitions and fuel . To ease the situation , the Luftwaffe sent an ad - hoc force of 300 Ju 52s , enabling the German Army to forge ahead . In some cases , bombers were diverted from combat operations to supply missions under the so - called " Stalingrad Transport Region force " . The stubborn Soviet defence at the Don River forced the Germans to commit more and more troops to an increasingly vulnerable front , leaving little in the way of reserves to back up the Axis divisions on either flank . Consequently , the Soviets launched several counterattacks on Army Group B ' s northern flank between Stalingrad and Voronezh . Between 20 – 28 August , 63rd Army together with 21st Army counterattacked near Serafimovich , forcing Italian Eighth Army to fall back . At the same time , 1st Guards Army attacked near Novo - Grigoryevskaja , extending its bridgehead . These and several other bridgeheads across the Don River , opposed by Eighth Italian and Second Hungarian Armies , would cause major difficulties for the Germans in the future . On 23 August , Sixth Army finally crossed the Don River , allowing Army Group B to establish a defensive line on one of its bends . The Sixth Army reached Stalingrad ' s northern suburbs later that day , beginning the Battle of Stalingrad . The Hungarian , Italian and Romanian armies deployed for this task were now from Stalingrad , which was also within reach of forward air bases . Consequently , bombers of " Luftflotte " 4 attacked the city , turning much of it to rubble . Soviet reports at the time asserted that civilian casualties between the 23 – 26 August , were 955 dead and 1 , 181 wounded . Although the final figures are likely to have been much higher than this preliminary total , reports of civilian casualties numbering tens of thousands were probably exaggerations by the Soviets . The two - pronged ground attack on Stalingrad involved the Sixth Army advancing from the north ( Kalach ) and Fourth Panzer Army coming up from the south ( Kotelnikovo ) . In the first few days , XIV Panzer Corps opened a narrow breach between the main Sixth Army ' s body and the northern Stalingrad suburbs at the Volga River while in the south , heavy Soviet resistance prevented Fourth Panzer Army from making any headway . On 29 August another attempt was made with Hoth turning his forces west directly through the center of the 64th Army . The attack brought unexpected success , and Hoth ' s men found themselves in the rear areas of both the 62nd and 64th Armies . This created a salient and opened the opportunity to encircle and cut off the 62nd Army . Hoth continued his drive and von Weichs ordered the Sixth Army to complete the encirclement , but a strong Soviet counterattack held up its advance for three vital days , enabling Soviet forces in the salient to escape and fall back towards Stalingrad . Despite this close escape , the rapid German advance caused considerable morale breakdown among the Soviet troops , who retreated in chaos , abandoning the outer defences of the city . After neutralizing the last limited local Soviet counterattacks , the Sixth Army resumed its offensive on 2 September and linked up with Fourth Panzer Army the following day . On 12 September , the Germans entered Stalingrad itself and fighting within the city began the next day . The Battle of Stalingrad . The advance into Stalingrad against the defenders of the 62nd Army was carried out by the worn out forces of the Sixth Army , while Fourth Panzer Army secured the southern flank . The city itself sprawled in a narrow , ribbon along the western side of the Volga River , which forced the Germans to conduct a frontal assault against the city , with the ruins of the city heavily favoring the defenders . To deal with the complete air superiority of the " Luftwaffe " , the commander of the 62nd Army , General Vasily Chuikov , ordered his troops to engage the Germans in close quarters fighting ( ' hugging ' the enemy ) , rendering the German superiority in combined arms tactics almost useless . The " Luftwaffe " nevertheless played a crucial role , as it suppressed Soviet artillery on the eastern bank of the Volga and caused heavy casualties to the Soviet attempts to reinforce the defenders over the river . From mid September until early November , the Germans started three heavy assaults against the city , gradually but steadily reducing the perimeter the Soviets held more and more . Although Soviet casualties in the macabre street fighting were staggering , the German troops also took enormous losses . By mid November , the Soviet - held territory was reduced to just four shallow bridgeheads , with the front lines only from the river . Anticipating victory , substantial numbers of " Luftwaffe " aircraft were withdrawn to the Mediterranean in early November , to support the Axis operations in Tunisia . Although Sixth Army now held about 90 % of the city , it was nevertheless unable to destroy the last pockets of resistance in time . On 19 November , the Soviets launched Operation Uranus , a massive two - pronged counteroffensive against Sixth Army ' s flanks . With Sixth Army almost completely embroiled in the battle for the city and Fourth Panzer Army exhausted , these flanks were mainly guarded by Romanian , Hungarian , and Italian soldiers . Third Romanian Army , situated on the Don River west of Stalingrad , as well as Fourth Romanian Army to the Southeast of Stalingrad , had been under constant Soviet attack since September . Third Romanian Army had been transferred from the Caucasus on 10 September to take over the Italian positions on the Don and oppose the Soviet bridgeheads . The Romanians , who were in the direct path of the Soviet offensive , were therefore understrength and had only around six modern anti - tank guns " per " division . The bulk of the German tank reserve , the 48th Panzer Corps , consisted of roughly 180 tanks , of which half of them were obsolete Panzer 35 ( t ) s . As a result , the two Romanian armies were routed , and the Sixth Army as well as parts of Fourth Panzer Army were trapped inside Stalingrad . Hitler , against the advice of most of the involved army commanders , personally ordered Sixth Army to remain on the defensive rather than try to break out . It was intended the Army be re - supplied by air ; since the required quantity of supplies was far beyond " Luftwaffe " delivery capabilities , the fighting strength of Sixth Army diminished and the Soviets gained the upper hand inside the city . To stabilise and restore the situation on the Eastern Front , Army Group Don ( " Heeresgruppe Don " ) under Field Marshal von Manstein was created to fill the gap between Army Group A and B . On 12 December , a relief operation called Operation Winter Storm began . Spearheaded by some of the first Tiger tank s , the offensive was able to drive within of the southern edge of the Sixth Army ' s front , although the trapped German forces made no attempt to link up with the relief forces . The failed relief efforts led to a siege that lasted for almost three additional months , during which the Sixth Army was ultimately destroyed . Soviet counter strokes and aftermath . Following on from the success of Uranus , the Red Army began Operation Saturn , a plan designed to cut off the entire German Army Group A and all troops east of Rostov from the rest of the " Heer " . As a result of Manstein ' s relief operation at Stalingrad , Soviet forces had been redeployed , so the operation was now dubbed " Little Saturn " and its objectives scaled down . The operation targeted Eighth Italian Army and the remnants of Third Romanian Army and led to the destruction of most of the Italian forces . Although on the verge of collapse , Army Group B and Don were able to prevent a major Soviet breakthrough , but with Army Group A threatened with being cut off , it was ordered to withdraw from the Caucasus on 28 December . In the following months the Soviets launched several follow - up offensives , summing up as the Voronezh - Kharkov Strategic Offensive . The Ostrogozhsk – Rossosh Offensive , launched on 12 - 13 January , destroyed large parts of the Second Hungarian Army and the remnants of Eighth Italian Army at the Don southeast of Voronezh . With its southern flank in danger , the German Second Army was forced to withdraw from Voronezh and the Don . Those successful operations from November until January led Stavka to believe that they could deal a fatal blow to the Germans to decide the war in southern Russia . Operation Star , conducted by the Voronezh Front , was aimed at Kharkiv , Kursk , and Belgorod , and Operation Gallop , conducted by the Southwestern Front , was aimed at Voroshilovgrad , Donetsk and then towards the Sea of Azov to cut off all German forces east of Donetsk . The operations were launched simultaneously at the end of January and the Soviets were able to break through the German lines during the first days . In the north Kursk fell on 8 February and Kharkiv on 16 February after a German withdrawal , while in the south the Germans were pushed back to a line west of Voroshilovgrad . Facing this increasingly precarious situation , Army Group Don , B and parts of Army Group A were reunited as Army Group South under Manstein ' s command on 12 February . With the initial success of the Soviet offensives , the Kharkiv and Donbas operations were launched on 25 February . They were conducted by the newly formed Central Front led by Rokossovsky , which was made up from forces freed after the surrender of the German forces in Stalingrad on 2 February . The operations were aimed at Army Group Centre in the north and timed to coincide with the anticipated successes of the Soviet operations in the south . Despite those heavy blows , Manstein ' s forces , fighting a vigorous defense campaign , were not cut off and prepared for an own counteroffensive , which would lead to the Third Battle of Kharkov and the stabilisation of the front . The disaster at Stalingrad marked the failure of Case Blue . Thereafter all previous gains had been reversed by the end of 1943 , with the Kuban bridgehead , established at the Taman peninsula for a possible second thrust into the Caucasus , being the last to be evacuated on 9 October 1943 . Post - operation analysis . Due to the significant initial successes of the 1942 German summer offensive , the German command and especially Hitler expanded the already sophisticated plan even more , putting great strain on their forces . Hitler did not expect the Soviets to be able to launch a counteroffensive on the scale of Operation Uranus , and therefore deployed valuable units elsewhere on the front , while ordering the " Wehrmacht " to simultaneously strive for numerous goals . Any opposition to his fluctuating plans simply led to dismissal by Hitler , who interfered more and more in the command process . Overstretched by the vast area they had captured , the reduced capabilities of the " Heer " and its allies to defend this territory enabled the Soviets to mount a decisive offensive at Stalingrad , encircling a whole German army . Soon both sides concentrated largely on the epic struggle for the city , making the Caucasus campaign a secondary theatre . With Army Group B unable to hold the Volga line , subsequent Soviet operations threatened to cut off Army Group A in the Caucasus , and it was forced to withdraw . The surrender of Sixth Army was a serious blow to German morale in general and it proved a personal shock to Hitler . Nevertheless , despite the destruction of Sixth Army , the Soviets only caused the " Heer " to retreat from their advance towards the Caucasus , further delaying the final decision on the Eastern Front . The by now highly confident Soviet command overestimated its capabilities and pushed its forces deep into the German lines , to the limit of its supply lines , which led to a severe defeat at Kharkov and gave the Germans the opportunity to mount another large strategic offensive .