Operation Citadel (German: Unternehmen Zitadelle) was the German offensive operation in July 1943 against Soviet forces in the Kursk salient, proposed by Generalfeldmarschall Erich von Manstein during the Second World War on the Eastern Front that initiated the Battle of Kursk. The deliberate defensive operation that the Soviets implemented to repel the German offensive is referred to as the Kursk Strategic Defensive Operation. The German offensive was countered by two Soviet counter-offensives, Operation Polkovodets Rumyantsev (Russian: Полководец Румянцев) and Operation Kutuzov (Russian: Кутузов). For the Germans, the battle was the final strategic offensive that they were able to launch on the Eastern Front. As the Allied invasion of Sicily began, Adolf Hitler was forced to divert troops training in France to meet the Allied threats in the Mediterranean, rather than use them as a strategic reserve for the Eastern Front. Germany's extensive losses of men and equipment during the operation, though significantly lower than those suffered by the Soviets, delivered the Red Army the strategic initiative for the remainder of the war.
The Germans hoped to weaken the Soviet offensive potential for the summer of 1943 by cutting off a large number of forces that they anticipated would be in the Kursk salient. The Kursk salient, or bulge, was 250 kilometres (160 mi) long from north to south and 160 kilometres (99 mi) from east to west. The plan envisioned an envelopment by a pair of pincers breaking through the northern and southern flanks of the salient. Hitler believed that a victory here would reassert German strength and improve his prestige with his allies, who were considering withdrawing from the war. It was also hoped that large numbers of Soviet prisoners would be captured to be used as slave labour in the German armaments industry.
The Soviet government had foreknowledge of the German intentions, provided in part by the British intelligence services, and by the intelligence transmitted by the Lucy spy ring. Aware months in advance that the attack would fall on the neck of the Kursk salient, the Soviets built a defence in depth designed to wear down the German armoured spearhead. The Germans meanwhile delayed the offensive while they deployed their forces and waited for new weapons, mainly the new Panther tank but also larger numbers of the Tiger tank. This gave the Red Army time to construct a series of deep defensive belts. The defensive preparations included minefields, fortifications, artillery fire zones and anti-tank strong points, which extended approximately 300 km (190 mi) in depth. Soviet mobile formations were moved out of the salient and a large reserve force was formed for strategic counter-offensives.
Background
After the conclusion of the battle for the Donets, as the spring rasputitsa (mud) season came to an end in 1943, both the German and Soviet commands considered their plans for future operations. The Soviet Premier Joseph Stalin and some senior Soviet officers wanted to seize the initiative first and attack the German forces inside the Soviet Union, but they were convinced by a number of key commanders, including the Deputy Supreme Commander Georgy Zhukov, to assume a defensive posture instead. This would allow the German side to weaken themselves in attacking prepared positions, after which the Soviet forces would be able to respond with a counter-offensive.
Strategic discussions also occurred on the German side, with Erich von Manstein arguing for a mobile defence that would give up terrain and allow the Soviet units to advance, while the German forces would launch a series of sharp counterattacks against their flanks to inflict heavy attrition. But for political reasons, German Chancellor Adolf Hitler insisted that the German forces go on the offensive, choosing the Kursk salient for the attack. On 15 April 1943, the Führer authorized preparations for Unternehmen Zitadelle (Operation Citadel).
Operation Citadel called for a double envelopment, directed at Kursk, to surround the Soviet defenders of five armies and seal off the salient. Army Group Centre would provide General Walter Model's 9th Army to form the northern pincer. It would cut through the northern face of the salient, driving south to the hills east of Kursk, securing the rail line from Soviet attack. Army Group South would commit the 4th Panzer Army, under Hermann Hoth, and Army Detachment Kempf, under Werner Kempf, to pierce the southern face of the salient. This force would drive north to meet the 9th Army east of Kursk. Von Manstein's main attack was to be delivered by Hoth's 4th Panzer Army, spearheaded by the II SS Panzer Corps under Paul Hausser. The XLVIII Panzer Corps, commanded by Otto von Knobelsdorff, would advance on the left while Army Detachment Kempf would advance on the right. The 2nd Army, under the command of Walter Weiss, would contain the western portion of the salient.
Obstacles and postponements
The German offensive, originally slated to commence in the beginning of May, was postponed several times as the German leadership reconsidered and vacillated over its prospects, as well as to bring forward more units and equipment.
As soon as Operations Order 6 was issued, which dictated that the operation should be ready to start on six days' notice after 28 April, the Ninth Army, which was to command the offensive in the Army Group Center zone, protested that its deployment could not be completed by 3 May. At a 3 May meeting, Hitler conferred with Manstein, Kluge, Zeitzler, Guderian, Speer, Chief of Staff OKL Generaloberst Hans Jeschonnek, and Commanding General, Ninth Army, Generaloberst Walter Model. There followed a discussion on the problems Model expected the Ninth Army to encounter in breaking through a "well-fortified" Soviet front and the inability of the Panzer IV tanks to stand up to the new Soviet antitank weapons. Hitler closed the meeting without giving a decision, but indicated privately to Model that there would be a postponement. Manstein, Kluge, Zeitzler, Jeschonnek objected to the delay; Guderian and Speer objected to Citadel being executed at all because, even if successful, they argued, it would cause heavy tank losses and upset plans for an increase in armor strength for the German forces. Hitler decided to let Citadel wait until June, by which time he expected to have tanks of a newer model (Tiger I) available in quantity. On 6 May, the OKH announced that Citadel was postponed to 12 June.
On 10 May, Guderian was summoned to the Reich Chancellery in Berlin, for a discussion on the production of the Panther tank, and potential delays in its program. After the conference, Guderian asked for an audience with Hitler, in which Keitel, Guderian's Chief of Staff Wolfgang Thomale, and Karl Saur of the Armaments Ministry were also present. There, as Guderian reports in his memoirs, he asked the Führer, "Why do you want to attack in the East at all? How many people do you think even know where Kursk is? It is a matter of profound indifference to the world whether we hold Kursk or not. Why do we want to attack in the East at all this year?" Hitler, according to Guderian, responded:
You're quite right. Whenever I think of this attack my stomach turns over.
Hitler assured Guderian that there was yet no commitment to the operation. However, at a May meeting of high Nazi Party officials, Hitler compared the current situation in the Eastern front to the predicament of the party in 1932, when it seemed to go down in political defeat at the hands of Franz von Papen and Hindenburg. He stated
In 1932, we attained victory only by stubbornness that sometimes looked like madness; so, too, we will achieve it today.
In the first weeks of June, the forces for Citadel were at their peak strength. On 18 June, the OKW Operations Staff submitted a proposal that Citadel be abandoned, and that all troops that could be spared should be deployed into strategic reserves for the defense of Italy and the Balkans, as well as Germany proper. On the same day, Hitler responded that he "fully appreciated" the General Staff's view, but had decided to go ahead; two days later, he set the time for 5 July.
The Soviet leadership, through their intelligence agencies and foreign sources, had been informed about the German intentions, and therefore the multiple delays by the German high command, OKW, allowed them a great deal of time to prepare their defences. Employing defence in depth, they constructed a series of defensive lines to wear down the attacking panzer formations. Three belts made up of extensive minefields, anti-tank ditches and anti-tank gun emplacements were created. Behind those were an additional three belts, which were mostly unoccupied and less fortified. The Voronezh Front, commanded by General Nikolai Vatutin, was tasked with defending the southern face of the salient. The Central Front, commanded by Konstantin Konstantinovich Rokossovsky, defended the northern face. Waiting in reserve was the Steppe Front, commanded by Ivan Konev. In February 1943, the Central Front had been reconstructed from the Don Front, which had been part of the northern pincer of Operation Uranus and had been responsible for the destruction of the 6th Army at Stalingrad.
Preliminary actions
Fighting started on the southern face of the salient on the evening of 4 July 1943, when German infantry launched attacks to seize high ground for artillery observation posts before the main assault. During these attacks a number of Red Army command and observation posts along the first main belt of defence were captured. By 16:00, elements of the Panzergrenadier Division "Großdeutschland", 3rd and 11th Panzer Divisions had seized the village of Butovo and proceeded to capture Gertsovka before midnight. At around 22:30, Vatutin ordered 600 guns, mortars and Katyusha rocket launchers, of the Voronezh Front, to bombard the forward German positions, particularly those of the II SS Panzer Corps.
To the north, at Central Front headquarters, reports of the anticipated German offensive came in. At around 02:00 5 July, Zhukov ordered his preemptive artillery bombardment to begin. The hope was to disrupt German forces concentrating for the attack, but the outcome was less than hoped for. The bombardment delayed the German formations, but failed in the goal of disrupting their schedule or inflicting substantial losses. The Germans began their own artillery bombardment at about 05:00, which lasted 80 minutes in the northern face and 50 minutes in the southern face. After the barrage, the ground forces attacked, aided by close air support provided by the Luftwaffe.
In the early morning of 5 July, the VVS launched a large raid against German airfields, hoping to destroy the Luftwaffe on the ground. This effort failed, and the Red Army air units suffered considerable losses. The VVS lost 176 aircraft on 5 July, compared to the 26 aircraft lost by the Luftwaffe. The losses of the VVS 16th Air Army operating in the northern face were lighter than those suffered by the 2nd Air Army. The Luftwaffe was able to gain and maintained air superiority over the southern face until 10–11 July, when the VVS began to obtain ascendency but the control of the skies over the northern face was evenly contested until the VVS began to gain air superiority on 7 July, which it maintained for the rest of the operation.
Operation along the northern face
Model's main attack was delivered by XLVII Panzer Corps, supported by 45 Tigers of the attached 505th Heavy Tank Battalion. Covering their left flank was XLI Panzer Corps, with an attached regiment of 83 Ferdinand tank destroyers. On the right flank, XLVI Panzer Corps consisted at this time of four infantry divisions with just 9 tanks and 31 assault guns. To the left of XLI Panzer Corps was XXIII Army Corps, which consisted of the reinforced 78th Assault Infantry Division and two regular infantry divisions. While the corps contained no tanks, it did have 62 assault guns. Opposing the 9th Army was the Central Front, deployed in three heavily fortified defensive belts.
Initial German advance
Model chose to make his initial attacks using infantry divisions reinforced with assault guns and heavy tanks, and supported by artillery and the Luftwaffe. In doing so he sought to maintain the armoured strength of his panzer divisions to be used for exploitation once the Red Army defences were breached. Once a breakthrough had been achieved the panzer forces would move through and advance towards Kursk. Jan Möschen, a major in Model's staff, later commented that Model expected a breakthrough on the second day. If a breakthrough was achieved, the briefest delay in bringing up the panzer divisions would give the Red Army time to react. His corps commanders, however, thought a breakthrough extremely unlikely.
Following a preliminary bombardment and Red Army counter bombardments, the 9th Army opened its attack at 05:30 on 5 July. Nine infantry divisions and one panzer division, with attached assault guns, heavy tanks, and tank destroyers, pushed forward. Two companies of Tiger tanks were attached to the 6th Infantry Division, and were the largest single grouping of Tigers employed that day. Opposing them were the 13th and 70th Armies of the Central Front.