Operation Uranus (19–23 November 1942) was a Soviet strategic operation on the Eastern Front of World War II which led to the encirclement of Axis forces in the vicinity of Stalingrad: the German Sixth Army, the Third and Fourth Romanian armies, and portions of the German Fourth Panzer Army. The Red Army carried out the operation at roughly the midpoint of the five-month long Battle of Stalingrad, aiming to destroy German forces in and around Stalingrad. Planning for Operation Uranus had commenced in September 1942, and developed simultaneously with plans to envelop and destroy German Army Group Center (Operation Mars) and German forces in the Caucasus.
Due to the length of the front lines created by the German 1942 summer offensive, which had aimed at taking the Caucasus oil fields and the city of Stalingrad, German and other Axis forces were over-extended. The German decision to transfer several mechanized divisions from the Soviet Union to Western Europe exacerbated their situation. Furthermore, Axis units in the area were depleted by months of fighting, especially those which had taken part in the struggle for Stalingrad. The Germans could only count on the XLVIII Panzer Corps, which had the strength of a single panzer division, and the 29th Panzergrenadier Division as reserves to bolster their Romanian allies guarding the German Sixth Army's flanks. These Romanian armies lacked the heavy equipment to deal with Soviet armor. In contrast, the Red Army deployed over one million personnel for the offensive. Soviet troop movements were not without problems: concealing their build-up proved difficult, and Soviet units commonly arrived late due to logistical issues. Operation Uranus was first postponed by the Soviet high command (Stavka) from 8 to 17 November, then to 19 November.
At 07:20 Moscow time on 19 November, Soviet forces assaulted the northern flank of the Axis forces at Stalingrad; attacks in the south began the next day. Although the Romanian units succeeded in repelling the first Soviet attacks, by the end of 20 November the Third and Fourth Romanian armies were in headlong retreat, as the Red Army bypassed several German infantry divisions. German mobile reserves proved too weak to parry the Soviet mechanized spearheads, while the Sixth Army did not react quickly or decisively enough to disengage German armored forces in Stalingrad and re-orient them to countering the impending threat. By late 22 November, the northern and southern Soviet forces linked up at the town of Kalach, encircling some 290,000 Axis personnel east of the Don River. Instead of attempting to break out of the encirclement, German leader Adolf Hitler decided to keep Axis forces in Stalingrad and to resupply them by air.
Background
On 28 June 1942, the Wehrmacht began its offensive against Soviet forces opposite of Army Group South, codenamed Case Blue. After breaking through Red Army forces by 13 July, German forces encircled and captured the city of Rostov. Following the fall of Rostov, Hitler split German forces operating in the southern extremity of the southern Russian SFSR in an effort to simultaneously capture the city of Stalingrad and the Caucasus oil fields. The responsibility to take Stalingrad was given to the Sixth Army, which immediately turned towards the Volga River and began its advance with heavy air support from the Luftwaffe's Luftflotte 4. On 7 August, two German panzer corps were able to flank and encircle a Soviet force of 50,000 personnel and approximately 1,000 tanks, and on 22 August German forces began to cross the Don River to complete the advance towards the Volga. The following day, the Battle of Stalingrad began when vanguards of the Sixth Army penetrated the suburbs of the city.
By November, the Sixth Army had occupied most of Stalingrad, pushing the defending Red Army to the banks of the Volga River. By this stage, there were indications of an impending Soviet offensive which would target Wehrmacht forces around the city, including increased Soviet activity opposite the Sixth Army's flanks, and information gained through the interrogation of Soviet prisoners. The German command remained focused upon finalizing its capture of Stalingrad and were unsure of where or when the counterattack would take place. Actions were taken to provide a reserve behind the Italian and Romanian armies, with 6th Panzer Division and two additional infantry divisions ordered to Russia from France. However, this move would only be completed by December. Head of Army General Staff General Franz Halder had been dismissed in September after his efforts to warn about the danger which was developing along the over-extended flanks of the Sixth Army and the Fourth Panzer Army. As early as September, the Soviet Stavka (high command) began planning a series of counteroffensives to encompass the destruction of German forces in the south, fighting in Stalingrad and in the Caucasus, and against Army Group Center. Ultimately, command of Soviet efforts to relieve Stalingrad was put under the leadership of General Aleksandr Vasilevsky.
The Stavka developed two major operations to be conducted against Axis forces near Stalingrad, Uranus and Saturn, and also planned for Operation Mars, designed to engage German Army Group Center in an effort to distract reinforcements and to inflict as much damage as possible. Operation Uranus involved the use of large Soviet mechanized and infantry forces to encircle German and other Axis forces directly around Stalingrad. As preparations for the offensive commenced, the attack's starting points were positioned on stretches of front to the rear of the German Sixth Army, largely preventing the Germans from reinforcing those sectors quickly where Axis units were too overstretched to occupy effectively. The offensive was a double envelopment; Soviet mechanized forces would penetrate deep into the German rear, while another attack would be made closer to the German Sixth Army in an effort to attack German units there directly in the rear. While the Red Army prepared, the German high commanders—influenced by their belief that the Red Army, building up opposite German Army Group Center to the north, was incapable of mounting a simultaneous offensive in the south—continued to deny the possibility of an impending Soviet offensive.
Comparison of forces
Axis
Case Blue involved German and other Axis forces sprawled out across a front over 480 kilometers (300 mi) wide and several hundred kilometers deep, while the decision to conquer Stalingrad had stretched Axis forces even more thinly by drawing away personnel eastwards. For example, in early July, the Sixth Army was defending a 160-kilometer (100 mi) line, while also committing to an offensive which involved a distance of around 400 kilometers (250 mi). Army Group B, which was split from Army Group South (the forces operating around the Caucasus, were named Army Group A), seemed strong on paper: it included the Second and Sixth German, Fourth Panzer, Fourth and Third Romanian, Eighth Italian, and Second Hungarian Armies. Army Group B had the 48th Panzer Corps, which had the strength of a weakened panzer division, and a single infantry division as reserves. For the most part the German flanks were held by arriving non-German Axis armies, while German forces were used to spearhead continued operations in Stalingrad and in the Caucasus.
While Adolf Hitler expressed confidence in the ability of non-German Axis units to protect German flanks, in reality these units relied on largely obsolete equipment and horse-drawn artillery, while in many cases the harsh treatment of enlisted personnel by officers caused poor morale. In regard to mechanization, the First Romanian Armored Division was equipped with around 100 Czech-built R-2 tanks, armed with a 37-millimeter (1.5 in) gun, ineffective against the armor of Soviet T-34 tanks. Similarly, their 37-millimeter (1.5 in) PaK anti-tank guns were also antiquated and they were largely short of ammunition. Only after repeated requests did the Germans send the Romanian units 75-millimeter (3.0 in) PaK guns; six per division. These units were extended over very large sections of front; for example, the Third Romanian Army occupied a line 140 kilometers (87 mi) long, while the Fourth Romanian Army protected a line no less than 270 kilometers (170 mi) long. The Italians and Hungarians were positioned at the Don, west of the Third Romanian Army.
Generally, German forces were in no better shape; they were weakened by months of fighting the Red Army, and, while Stavka raised new armies, the German high command attempted to maintain its existing mechanized units. Furthermore, during the course of the German offensive between May and November 1942, two motorized divisions, the elite Leibstandarte and the Großdeutschland, were redeployed from Army Group A to the West, to provide a mechanized reserve in case of an Allied landing in France. The Sixth Army had also suffered many casualties during the fighting in the city of Stalingrad proper. In some cases, such as that of the 22nd Panzer Division, their equipment was no better than that of the First Romanian Armored Division. German formations were also overextended along large stretches of front; the XI Army Corps, for example, had to defend a front around 100 kilometers (62 mi) long.
Soviet
The Red Army allocated an estimated 1,100,000 personnel, 804 tanks, 13,400 artillery pieces and over 1,000 aircraft for the upcoming offensive. Across the Third Romanian Army, the Soviets placed the redeployed 5th Tank Army, as well as the 21st and 65th Armies in order to penetrate and overrun the German flanks. The German southern flank was targeted by the Stalingrad Front's 51st and 57th Armies, led by the 13th and 4th Mechanized Corps; these would punch through the Fourth Romanian Army, in order to link up with the 5th Tank Army near the town of Kalach. In total, the Soviets had amassed 11 armies and various independent tank brigades and corps.
Preparations for the offensive were, however, far from perfect; on 8 November, Stavka issued orders to postpone the launch date of the operation, because transportation delays had prevented many units from being able to move into place. In the meantime, units at the front went through a number of war games to practice repelling an enemy counterattack and exploiting a breakthrough with mechanized forces. These movements were masked through a deception campaign by the Soviets, including the decrease of radio traffic, camouflage, operational security, using couriers for communication instead of radio, and active deception, such as increasing troop movements around Moscow. Troops were ordered to build defensive fortifications, to offer false impressions to the Germans, while fake bridges were put up to divert attention from the real bridges being built across the Don River. The Red Army also stepped up attacks against Army Group Center and set up dummy formations to maintain the idea of a main offensive against German forces in the center.
The Soviet Stalingrad Front forces were subject to heavy bombardment, making mobilization more difficult. The 38 engineer battalions allocated to the front were responsible for ferrying ammunition, personnel and tanks across the Volga River while carrying out minor reconnaissance along sections of the front which were to be the breakthrough points of the impending offensive. In three weeks the Red Army transported around 111,000 soldiers, 420 tanks and 556 artillery pieces across the Volga.
On 17 November Vasilevsky was recalled to Moscow, where he was shown a letter written to Stalin by General Volsky, commander of the 4th Mechanized Corps, who urged calling off the offensive. Volsky believed the offensive as planned was doomed to failure due to the state of the forces earmarked for the operation; he suggested postponing the offensive and redesigning it entirely. Many Soviet soldiers had not been issued with winter garments, and many died of frostbite, "due to the irresponsible attitude of commanders". Although Soviet intelligence made honest efforts to collect as much information as possible on the disposition of the Axis forces arrayed in front of them, there was not much information on the state of the German Sixth Army. Vasilevsky wanted to call off the offensive. The Soviet commanders, overruling Vasilevsky, agreed the offensive would not be called off, and Stalin personally rang Volsky, who reiterated his intention to carry out the operation if ordered to do so.
Soviet offensive
Operation Uranus, postponed until 17 November, was again postponed for two days when Soviet General Georgy Zhukov was told the air units allotted to the operation were not ready; it was finally launched on 19 November. Shortly after 5 a.m. Lieutenant Gerhard Stöck, posted with the Romanian IV Army Corps on the Kletskaya sector called Sixth Army headquarters housed in Golubinsky, offering intelligence on a pending attack which would occur after 05:00 that morning; however, because his call had come in after five and false alarms were common during this time, the duty officer on the other end of the line was not keen on waking the Army Chief of Staff, General Arthur Schmidt. Although Soviet commanders suggested postponing the bombardment due to poor visibility from thick fog, front headquarters decided to proceed. At 07:20 Moscow time (05:20 German time) Soviet artillery commanders received the codeword "Siren", prompting an 80-minute artillery bombardment directed almost entirely against the non-German Axis units protecting the German flanks. At 07:30, the Katyusha rocket-launchers fired the first salvos and were soon joined by the 3,500 guns and mortars stretching along the few breakthrough sectors in front of the Third Romanian Army and the northern shoulder of the German Sixth Army's flank. Although thick fog prevented the Soviet artillery from correcting their aim, their weeks of preparation and ranging allowed them to lay down accurate fire on enemy positions along the front. The effect was devastating, as communication lines were breached, ammunition dumps destroyed and forward observation points shattered. Many Romanian personnel who survived the bombardment began to flee to the rear. Soviet heavy artillery aimed at Romanian artillery positions and second-echelon formations also caught the retreating Romanian soldiers.