The '2nd Iassy-Kishinev Strategic Offensive Operation' was the Soviet strategic offensive, following the '1st Iassy-Kishinev Offensive Operation', by the 2nd Ukrainian Front and 3rd Ukrainian Front, commanded by General Rodion Ya. Malinovsky and General Fyedor I. Tolbukhin respectively, to tackle Generaloberst Johannes Friessner’s Heeresgruppe 'Südukraine' in order to reclaim the Moldovan Soviet Socialist Republic and destroy the Axis forces in the region, thereby paving the way for a Soviet advance into Romania and the Balkans (20/29 August 1944).
Comprising two sub-operations, in the form of the 'Iassy-Focșani Offensive Operation (20/29 August) and 'Kishinev-Izmail Offensive Operation' (20/29 August), this undertaking resulted in the encirclement and complete decimation of the German forces, thereby furthering the Soviet army’s strategic advance deep into the southern part of eastern Europe, and also persuaded Romania to switch allegiance from the Axis powers to the USSR.
During the previous months of 1944, the German armies had been driven back along the whole of the Eastern Front, and by May 1944 Heeresgruppe 'Südukraine' (commanded up to 20 July by Generaloberst Ferdinand Schörner) had been forced back toward the pre-war Romanian frontier with the USSR, but nonetheless managed to establish a defensive line along the Dniestr river. However, the Soviet forces had managed to won two bridgeheads on the southern side of the Dniestr river before a temporary calm returned to the sector, offering the Germans the opportunity to rebuild their disarrayed and understrength formations.
Up to June Heeresgruppe 'Südukraine' had been among the most powerful German formations in terms of its armoured strength, but during the summer lull on its sector of the Eastern Front it had lost much of this armoured strength as formations were shifted to more active sectors, namely those of Schörner’s Heeresgruppe 'Nord' and Generalfeldmarschall Walter Model’s Heeresgruppe 'Mitte', in the vain hope that they might able to stem the Soviet advances into the Baltic states, Belorussia, northern Ukraine and Poland. On the eve of the '2nd Iassy-Kishinev Strategic Offensive Operation', therefore, the only armoured formations left to Heeresgruppe 'Südukraine' were General de brigadâ Radu Korne’s Romanian 1st Rumania Mare Armoured Division and two German formations in the form of Generalleutnant Hans Tröger’s 13th Panzerdivision and Generalleutnant August Schmidt’s 10th Panzergrenadierdivision.
The Soviet summer offensive against Generalfeldmarschall Ernst Busch’s (from 28 June Model’s) Heeresgruppe 'Mitte' and Model’s (from 28 June Generaloberst Josef Harpe’s) Heeresgruppe 'Nordukraine' had already driven an huge blunt wedge into the centre of the German position on the Eastern Front. The flanks, reaching out to the Arctic Ocean in the north and the Black Sea in the south, were still held by the Germans and their allies, but were stretched to breaking point and on the verge of snapping if subjected to only the slightest of pressures. Though much of the strain under which the Germans and their allies were suffering was not superficially evident, it was nonetheless real and still very acute.
By 25 July, when Schörner and Friessner were summoned in the early morning hours to exchange places in command of Heeresgruppe 'Nord' and Heeresgruppe 'Südukraine', under Schörner’s driving control Heeresgruppe 'Südukraine' had experienced more than two months of comparative inaction ruffled only by the strenuous training and fitness programme demanded by its commander. The Soviets had taken so many divisions from this part of the Eastern Front that the Oberkommando des Heeres ordered the army group to do make every effort to pin those which were left and thereby prevent the extraction of further Soviet formations to strengthen their forces on other sectors of the front. The front line had not changed since the end of the Soviet spring offensive. On the army group’s left, in a curving line from Kuty to a point lying to the east of Iassy, General Otto Wöhler’s Armeegruppe 'Wöhler', comprising Wöhler’s own German 8th Army divided in two with General de corp de armatâ Mihail Racovita’s Romanian 4th Army sandwiched between them, held a sector of which about half lay in the eastern part of the Carpathian mountains and the other half on an east/west line across Moldova to the north of Târgu Frumos and Iassy. On the army group’s right, General Maximilian Fretter-Pico’s German 6th Army extended from a point to the east of Iassy to the Dniestr river below Dubăsari and then followed the river to about the centre of the Soviet bridgehead below Tiraspol, where it met the left of General de armatâ Petre Dumitrescu’s Romanian 3rd Army on the line of the river’s lower reaches. The 6th Army and Romanian 3rd Army constituted Dumitrescu’s Armeegruppe 'Dumitrescu'.
Two major waterways, the Prut and Siret rivers, cut the army group’s zone from north to south, and the Soviet forces were across the upper reaches of both. Rugged, wooded terrain in the areas of Târgu Frumos and Iassy partly offset that disadvantage, but only so long as long as the army group retained sufficient German strength to bolster the Romanian formations. The most important operational-level change during the early summer was that the retreat of Heeresgruppe 'Nordukraine' deep into Poland had left Heeresgruppe 'Südukraine' in essence stranded to the east of the Carpathian mountains, where Malinovsky’s 2nd Ukrainian Front and Tolbukhin’s 3rd Ukrainian Front faced the Armeegruppe 'Wöhler' and Armeegruppe 'Dumitrescu' respectively.
At the time of the change in command on 25 July, the principal concern of the staff of Heeresgruppe 'Südukraine' was to determine how great and indeed dangerous were the strains beneath the thin appearance of the quiet front and what could be achieved before these strains reached breaking point. Two days before his translation to Heeresgruppe 'Nord', Schörner wrote to Adolf Hitler to emphasise that many of Romania’s leading military and political figures were wavering in their adherence to the Axis and trying to establish contacts with the Allies and that Maresal al România Ion Antonescu, the Romanian leader, was losing his grip on the country, and suggested that a personal meeting with Hitler might strengthen Antonescu’s position.
On 25 July the army group staff drafted a report stating that after being forced to transfer six Panzer divisions, two infantry divisions, and two self-propelled assault gun brigades in the past month, the army group could no longer hold its front against a major offensive, and recommended that the army group be authorised in advance to fall as soon as such an offensive started. The report was not sent, however, apparently because the estimate of Friessner, the new commander-in-chief, was more optimistic.
The most pressing German concern, at least in the short term, was Romania’s internal situation. Heeresgruppe 'Südukraine' was wholly dependent on the indifferent Romanian railway system for its logistical support and therefore compelled in large part to subsist off the local economy, but had no right to make any intervention in Romania. Thus everything had to be decided between Bucharest and Berlin. Moreover, by a time late in July the army group staff was convinced that on the most important question, that of Romanian loyalty to the Axis alliance, matters were seriously out of balance. The fact that Antonescu, on whose personal authority alone the alliance was based, no longer possessed that authority, seemed to be open knowledge within Romania to all but Antonescu himself, Manfred Freiherr von Killinger, the German ambassador in Rumania, and General Erik Hansen, the chief of the German military mission. The latter two were the two senior German representatives, political and military, in Romania. Both von Killinger, a long-time Nazi turned diplomat, and Hansen, an energetic but inflexible officer, were blinded by their own personal faith in Antonescu. Both men therefore reinforced the tendency, which was already widely spread within Hitler’s inner circle, to confuse Antonescu’s personal loyalty with that of the Romanian forces and people. The staff of Heeresgruppe 'Südukraine' was sure that Antonescu remained in power only because his many opponents were unwilling, but ever less unwilling, to take the risk of attempting to remove him, and that the entire country remained in the war solely because its fear of the Soviets was still slightly greater than its desire for peace.
On 1 August, reflecting on the changes which might sweep south-eastern Europe after Turkey ended diplomatic relations with Germany on the following day, Friessner ordered each of his two German armies to establish a mobile regiment for use in countering 'possible surprises in Romanian territory'. Oddly and, as it eventuated, fatefully, Friessner concentrated his attention almost exclusively on the dangers which would arise in the event of Romania’s defection. What Friessner and his army group staff did no consider was the equally vital question, given the fact that the Romanians held 160 miles (260 km) of the army group’s 390-mile (625-km) front, of what remained, if any at all, of the Romanian army’s will to continue the fight.
During the first week of August, Antonescu travelled to Rastenburg in East Prussia to speak with Hitler. The two leaders met under a darkening cloud of German reverses on the Western Front as well as the Eastern Front, and in an atmosphere of mutual suspicion and recrimination. Ultimately, however, neither of the leaders had any real alternative but to tell the other what he wished to hear. In May, after more or less open negotiations in Cairo with the Americans, British and Soviets, Antonescu had rejected one set of armistice terms. When secret negotiations conducted, over the same period and in Sweden, with the USSR had led to the offer of somewhat more lenient terms, Antonescu had again not been able to steel himself to accept.
The report about the meeting of Hitler and Antonescu which reached Heeresgruppe 'Südukraine' was positive. Hitler had told Antonescu what was being done to restore Germany’s situation, and each man had promised the other 'everything possible'. Yet in the transmission of the report, someone had added that it merely remained to be seen how far the promises would be carried out.
As many of the individual points which had been discussed arose out of its presence in Romania and because the time appeared appropriate to raise fundamental questions, the army group had sent its operations officer, Oberst Ivo-Thilo von Trotha, to Führer headquarters during Antonescu’s visit, and Friessner also sent a letter in which he told Hitler that the army group could hold its front if it did not lose any more divisions, but nonetheless had to be prepared for all eventualities. Friessner recommended that the army group be given control of all German military activities in Romania and that a single responsible political agency be appointed with which the army group could collaborate. On Friessner’s instructions, von Trotha told Generaloberst Heinz Guderian, the chief of the army general staff, that the Oberkommando des Heeres would have to reconcile itself to authorising the army group to fall back to the line of the Carpathian mountains and lower part of the Danube river if the army group had to give up more divisions or if the Romanians became still less reliable. After talking to Hitler, Guderian replied that he hoped, should events take such a turn, to be able to give the necessary order in time. The prospect that any such an order would in fact be given faded, however, after the talks with Antonescu revealed that despite the fact that he had argued in the spring for a withdrawal to the Carpathian/Danube line, he had meantime become sure that the sacrifice of more Romania territory would be fatal.
With Generalfeldmarschall Wilhelm Keitel, the head of the Oberkommando der Wehrmacht, von Trotha raised the question of having Friessner named commander of the armed forces in Romania, and also suggested the replacement of Hansen by an officer able to represent the German interest more forcefully. Keitel initially seemed to be impressed but, after the talks with Antonescu, said he saw no need for any changes because Romania would remain at Germany’s side whatever the circumstances. In overall terms, therefore, the shaky German and Romanian concord was notionally patched once more, but only at the expense of Heeresgruppe 'Südukraine'.
On 8 August German air reconnaissance for the first time detected Soviet troop movements to the east of the Prut river, and the revelation that there was heavy traffic toward and light traffic away from the front could serve to confirm only that men, weapons and equipment were reinforcing the Soviet front and not being removed for transfer to other sectors of the Eastern Front.
Even so, on 13 August the Oberkommando des Heeres removed yet another division from the army group, this raising the total number of divisional transfers from the army group to 11 since June, and reducing the army group’s overall strength by almost one-third or, in the case of Panzer divisions, almost three-fourths. On the same day a rumour that Antonescu had been overthrown led to a period almost of panic in the army group’s rear areas. The Armeegruppe 'Wöhler' reported on 16 August that the Soviets were prepared to attack within two days at the most, probably in the area to the west of Iassy, to drive a wedge between Iassy and Târgu Frumos. The Romanians, the Armeegruppe 'Wöhler' said, were wholly confident. By the afternoon of 19 August, after Malinovsky’s 2nd Ukrainian Front had launched artillery-supported probing attacks along the front held by Armeegruppe 'Wöhler', Heeresgruppe 'Südukraine' expected to come under major attack on the following day in the area to the west of Iassy, and predicted a secondary attack to the south of Tiraspol.
The Soviet maskirovka deception effort before the launch of the offensive worked notably well, and the German command believed that the movement of Soviet forces along the front line was a result of a troop transfer to the north, the exact positions of the Soviet formations facing the Axis forces not becoming clear until the last hours of the lull. The Stavka’s plan for the operation was based on a double envelopment of the German and Romanian armies by the 2nd and 3rd Ukrainian Fronts. The 2nd Ukrainian Front was to break through north of Iaşi, and then commit mobile formations to seize the Prut river crossings before the retreating formations of General Maximilian Fretter-Pico’s German 6th Army could reach them. The 2nd Ukrainian Front was then to commit General Leytenant Andrei G. Kravchenko’s 6th Tank Army to seize the Siret river crossings and the Focşani gap, the latter a fortified line between the Siret and Danube rivers. The 3rd Ukrainian Front was to attack out of its bridgehead across the Dniestr river near Tiraspol, and then commit its mobile formations with the task of heading north to link with the mobile formations of the 2nd Ukrainian Front, and thus trap the German forces near Chişinău. Following the successful encirclement, the 6th Tank Army and General Major Vladimir I. Zhdanov’s IV Guards Mechanised Corps were to be launched toward Bucharest and the Ploieşti oil fields.
As 20 August dawned, the weather was sunny and the day promised to become hot. The Soviet artillery laid down heavy barrages on two fairly narrow sectors, one to the north-west of Iassy and the other to the south of Tiraspol. By the time the infantry of 2nd and 3rd Ukrainian Fronts moved forward, several Romanian divisions were about to collapse. Two of the Romanian divisions of Armeegruppe 'Wöhler' protecting Iassy abandoned their positions without a fight. On the western side of the gap left by the fleeing Romanians, German reserves threw up a screening line, but on the east the Soviets continued to the south, turning into Iassy during the afternoon. To the south of Tiraspol, the Soviet offensive fell on the boundary between the German 6th Army and the Romanian 3rd Army. The 6th Army's right-flank corps, despite being that which was hit hardest, held its ground, but the Romanian division tying on the boundary collapsed, and this triggered the collapse of its southern neighbour. By the end of the day Friessner realised that the Romanian willingness to fight would fall below even its customary low standard, but how far below this the German commander had yet to learn.
According to Soviet figures, the 2nd Ukrainian Front and 3rd Ukrainian Front, with Marshal Sovetskogo Soyuza Semyon K. Timoshenko serving as their Stavka co-ordinator, had superiorities of slightly less than 2/1 in men, more than 2/1 in artillery and aircraft, and greater than 3/1 in tanks and self-propelled artillery. In overall terms, Malinovsky and Tolbukhin had 90 divisions and six tank and mechanised corps with 929,000 men. The main effort, by Kravchenko’s 6th Tank Army, General Leytenant Sergei G. Trofimenko’s 27th Army, General Konstantin A. Koroteyev’s 52nd Army and General Leytenant Ivan M. Managarov’s 53rd Army, was in Malinovsky’s sector to the north-west of Iassy. There the 6th Tank Army was committed during the afternoon of the first day, and by the fall of night this and the 27th Army were driving for an operational breakthrough. On the right, to the north of Târgu Frumos, General Leytenant Mikhail S. Shumilov’s 7th Guards Army and General Major Anatoli P. Gorshkov’s Cavalry-Mechanised Group 'Gorshkov' (Gorshkov’s own V Guards Cavalry Corps and General Leytenant Aleksei O. Akhmanov’s XXIII Tank Corps) were poised for a thrust to the south along the Siret river. Tolbukhin had General Major Mikhail N. Sharokhin’s 37th Army and General Leytenant Nikolai A. Gagen’s 57th Army and two independent corps (General Major Vladimir I. Zhdanov’s IV Guards Mechanised Corps and General Major Fedor G. Katkov’s VII Mechanised Corps) smashing their way out of the Tiraspol bridgehead. On their left General Leytenant Ivan T. Shlemin’s 46th Army had split its forces to envelop General de corp de armatâ Emanoil Leoveanu’s Romanian III Corps on the lower part of the Dniestr river.
The initial rupture of the 6th Army's sector was 25 miles (40 km) deep, and Soviet forces were destroying rear-area supply installations by the evening of 21 August. By 23 August the 13th Panzerdivision had ceased to exist as a coherent fighting force, and the 6th Army had been encircled to a depth of some 60 miles (100 km).
The main effort was made by Sharokhin’s 37th Army with General Major Dmitri A. Kupriianov’s LXVI Corps and General Major Grigori P. Kotov’s VI Guards Corps. The 37th Army was allocated a 2.5-mile (4-km) wide breakthrough front, and fought in two echelons, with two corps in the line and one corps in reserve. According to the plan, it was to break through the depth of the German/Romanian defence line in seven days to a depth of 68.5 to 74.5 miles (110 to 120 km) at the rate of 9.33 miles (15 km) per day during the first four days. Kupriianov’s LXVI Corps comprised two groupings (61st Guards Rifle and 333rd Rifle Divisions in the first echelon, and 244th Division in reserve), and attached to its were the 46th Gun Artillery Brigade, 152nd Howitzer Artillery Regiment, 184th and 1245th Tank Destroyer Regiments, 10th Mortar Regiment, 26th Light Artillery Brigade, 87th Recoilless Mortar Regiment, 92nd and 52nd Tank Regiments, 398th Assault Gun Regiment, two pioneer assault battalions, and two light flamethrower companies. There is no manpower information available for the divisions, but they probably had between 7,000 and 7,500 men each except for the 61st Guards Division, which mustered perhaps 8,000 and 9,000 men. The soldiers were prepared over the course of August by exercising in areas similar to those they had to attack, with emphasis on special tactics needed to overcome the particular enemy formations on their sector.
The 333rd Division did not organise itself in two echelons, and therefore had all three of its rifle regiments in the first echelon. The 61st Guards Division attacked in a standard formation of two regiment in the first echelon and one in reserve. This proved to be fortunate, because the right wing of the 188th Guards Rifle Regiment was unable to advance past the Ploptuschbej strongpoint. The 189th Guards Rifle Regiment on the left wing made good progress, though, as did 333rd Division on its left. The commander of 61st Guards Division therefore inserted his reserve, the 187th Guards Rifle Regiment, behind the 189th Guards Rifle Regiment to exploit the break-in. When darkness came, the 244th Division was inserted to break through the second line of defence, but became lost and arrived only at 23.00, by which time elements of 13th Panzerdivision were making a counterattack.
The German and Romanian opposition was found by Generalleutnant Georg Postel’s XXX Corps and General Anton Richard Freiherr von Mauchenheim und Bechtolsheim’s XXIX Corps with Generalmajor Rudolf Sperl’s 15th Division, Generalleutnant Karl-Erik Köhler’s 306th Division, General de brigadâ Alexandru Nasta’s Romanian 4th Mountain Division and General de brigadâ Atanasie Trincu’s Romanian 21st Division. The 13th Panzerdivision was in reserve. At the end of the first day the Romanian 4th Mountain Division and 21st Division had been almost completely destroyed, while the German 15th Division and 306th Division had been heavily damaged. Almost no German and Romanian artillery survived even the Soviet fire preparation. The 13th Panzerdivision counterattacked the LXVI Corps on the first day, and tried to stop its progress on the next day, but without success. As the result of recent reinforcement, at this time the 13th Panzerdivision was high in personnel strength but low in matériel strength, and its only armour comprised obsolescent PzKpfw IV battle tanks, Sturmgeschütz III assault guns and self-propelled anti-tank guns. At the end of the second day the division was incapable of meaningful resistance, let alone attack.
On the morning of the second day Friessner still thought the battle was about to evolve as he had expected. Although he lacked a clear picture of the Soviet strength, the army group’s intelligence branch seemed to confirm that the build-up had not been as great as the Soviets had recently gathered for a major offensive. Moreover, the main Soviet effort was falling on the Armeegruppe 'Wöhler', and there the second defensive line, the 'Trajan-Linie' on the heights behind Iassy, was believed to be very strong. When Antonescu arrived at the army group headquarters in the middle of the morning, he was informed by Friessner that the army group would close the front below Tiraspol and, taking everything it could from the Armeegruppe 'Dumitrescu', strengthen the northern sector of the front sufficiently to prevent a Soviet sweep behind the Prut river. Friessner believed that the Soviets could not bring as much strength to bear against Dumitrescu’s army grouping as they could against Wöhler’s army grouping and, having gone deeper the day before than expected, would probably have to pause to regroup. Up to this time a staunch advocate of the elastic defence, Antonescu now demanded that the front, including Iassy, must be held. Antonescu declared that he was personally answerable for every piece of Romanian territory lost, and that it was not just the fate of Bessarabia that was in the balance but the destiny of the whole Romanian people.
During the day every report from the front was more alarming than its predecessor. In the north Iassy had been was lost and the Soviets were expanding their offensive toward the west and Târgu Frumos. The armour of the Cavalry-Mechanised Group 'Gorshkov' drove through the 'Trajan-Linie' near Târgu Frumos, and armour-supported infantry reached the line along most of its length to the west of the Prut river. The Armeegruppe 'Wöhler' reported that five of its Romanian divisions had disintegrated. To the south of Tiraspol a 20-mile (32-km) gap opened between the German 6th Army and the Romanian 3rd Army.
During the afternoon Friessner decided to withdraw the Armeegruppe 'Dumitrescu' behind the Prut river and attempt to extricate sufficient German troops to reinforce the Armeegruppe 'Wöhler'. The army group and the operations branch of the Oberkommando des Heeres agreed that this could be only the first step of a withdrawal which could not end anywhere forward of the Carpathian/Danube river line. After being assured that Antonescu was now 'letting himself be guided solely by military considerations' and therefore had no objections, Hitler gave his approval during the night. By then the German 6th Army had been ordered to get as many of its men and as much of its heavy weapons, ammunition and supplies as it could behind the Prut river without delay. The staff of the 6th Army was among the first elements to depart as Soviet armour was already approaching the army’s headquarters in Komrat.
For the next two days the battle continued as it had begun. The Romanians forces, including even , even Korne’s supposedly elite 1st Rumania Mare Armoured Division, refused to fight. The Soviets swept rapidly to the south behind the Prut river and through the swept-aside centre of the Armeegruppe 'Dumitrescu', and the Germans were unable to commit anything against them. Behind the Prut river, the Soviet armoured spearheads reached Bârlad and Huși on 23 August.
The 3rd Ukrainian Front’s advance to the west passed Komrat nearly as far as the Prut river, and Shlemin’s 46th Army wheeled its left flank to the south-east and on its right attacked across the estuary of the Dniestr river to encircle the Romanian III Corps and one German division. The main German strength, which constituted the entire front from the Prut to the east of Iassy as far as Tiraspol, was falling back to the south-west rapidly, but not at a speed great enough to outpace the Soviet pincers closing in its rear.
Early in the evening of 23 August the headquarters of the Heeresgruppe 'Südukraine' learned that Antonescu had been summoned by King Mihai I during the afternoon: Antonescu’s administration had been dissolved, and Antonescu and its members arrested. Later the army group’s chief-of-staff, Generalmajor Helmuth Grolmann, spoke to von Killinger after the latter’s return from the palace, where the king had informed him that a new government had been formed and intended to reach an armistice with the Soviets. One condition which would not be accepted, the king had assured von Killinger, was that Romania should actually change sides and fight the Germans. The king’s broadcast to his people that evening was less reassuring, however, for he stated in this that Romania would join the Allied nations against the common enemy, Germany, and in was was effectively a declaration of war against Hungary, that Romania denounced the Treaty of Vienna of 30 August 1940 which had awarded the 'Szekler strip' in Transylvania to Hungary.
The contradiction in the king’s announcements arose apparently from the existence of two sets of armistice terms. Although the Romanian government in the public statement accepted the more stringent terms which had been offered by the USSR, USA and UK at the negotiations which began on the same night in Cairo, the Romanian delegation was under instruction to win amendments which would include the concessions which the USSR had offered in secret. The latter would have allowed Romania to declare itself neutral in the conflict with Germany and, of greater importance to the Romanians, proposed arrangements which would assure the continued existence of an independent Romanian state.
Shortly before 24.00 on 23/24 August, Friessner telephoned Hitler to give an account of the Romanian coup, and told him that he had taken command of all elements of the German armed forces in Romania and was preparing to fall back to the Carpathian/Danube line. Just after this the operations branch of the Oberkommando des Heeres passed on Hitler’s order to smash the coup, seize the king and his court associates, and turn the government over either to Antonescu or, in the event that the former prime minister and Conducător was no longer available, to a pro-German general. On learning that von Killinger, Hansen and General Alfred Gerstenberg, the Kommandierender General der deutschen Luftwaffe in Rumänien, were being held under guard in the German embassy, Friessner passed Hitler’s order to an SS general whom he located in an installation outside Bucharest. The SS general reported at 03.00 that troops would arrive from Ploieşti, where they had been part of the forces protecting the vital oil installations, within 90 minutes and would then move into the city.
Before the break of day, Hansen reported by telephone to Friessner that the Romanian war minister had declared that if the German measures against the new government were not stopped within an hour, the Romanian army would turn its weapons on the German forces, and Hansen added that he and the others with him were convinced the German forces were not strong enough to take Bucharest. When Friessner asked Hansen whether or not he was under restraint, the latter replied that he was. Friessner transmitted the gist of this conversation to Hitler’s headquarters, together with a reminder that the king had allegedly promised not to fight the Germans. A few minutes later Generaloberst Alfred Jodl, the chief of the Oberkommando der Wehrmacht’s staff, called to say that Hansen was not making a free report and that it would be best to make a clean sweep immediately. Almost simultaneously, a call came in from Gerstenberg, whom the Romanians had released in the belief that he would attempt to stop the forthcoming German action. Gerstenberg described the new Romanian government as a small and fearful clique, protected only by a thin screen of troops around the capital.
Friessner thereupon gave him command in the Bucharest area, and at 07.30 6,000 German troops began to close on the Romanian capital. Ten minutes later they met sharp resistance and were checked. Shortly before 12.00 Gerstenberg admitted that so far he had not been able to get past the outlying suburbs, and had taken the radio station but nothing else of significance. Friessner had meanwhile learned that not even one Romanian general was willing side with the Germans.
During the afternoon, and on Hitler’s orders, aircraft of Generalleutnant Alexander Holle’s Luftflotte IV bombed the royal palace and government buildings in Bucharest. The bombing not only gave the Romanian government an excuse for a complete breach with Germany, but also united national sentiment against the Germans. As the day ended, the deadlock around the capital continued while Gerstenberg waited for reinforcements from the forces controlled by Generalfeldmarschall Maximilian Reichsfreiherr von Weichs, the Oberbefehlshaber 'Südost'. Friessner had also requested troops from Hungary, but the Oberkommando der Wehrmacht had replied that it was receiving 'strange reports' from that country.
On 24 and 25 September, total disaster overtook Heeresgruppe 'Südukraine'. On 24 September the 2nd Ukrainian Front’s armoured spearheads took Bacău on the Siret river and crossed the Barladul river in an area downstream of Bârlad. Except for its rear-area elements, the 6th Army was concentrating to the south and east of Huși. Parts of two corps were to the west of the Prut river, but the main body was still to the east of this river. The army headquarters, which from its location in Focşani had only intermittent radio contact with its subordinate corps, wished to order the whole formation to turn to the south and attempt an escape across the lower Prut or Danube rivers. Assuming that the Soviets would close the crossings before the 6th Army could reach them, Friessner ordered a breakthrough to the west past Bacău to the Carpathian mountains.
On 25 September, the date in which Romania declared war on Germany, the destruction of the army group was almost complete. Heeresgruppe 'Südukraine' did not know what was happening to the 6th Army or what would happen to the numerous German units and installations within Romania. Friessner informed the Oberkommando des Heeres that what was left of his army group would have to retreat into Hungary and close the passes through the Carpathian mountain and the Transylvanian Alps. On 26 September Tolbukhin’s 3rd Ukrainian Front troops took Kagul, completing the encirclement of the 6th Army, and Malinovsky’s 2nd Ukrainian Front began to turn to the south-west across the lower part of the Siret river. Between the left flank of Generalleutnant Paul Klatt’s 3rd Gebirgsdivision in the Carpathian mountains to the west of Târgu Neamț and the mouth of the Danube river some 250 miles (400 km) to the south-east, Heeresgruppe 'Ukraine' had nothing resembling a front at any point. Even so, and perhaps inevitably in a situation so pregnant with disaster, Hitler intervened with an order to hold the line of the Carpathian mountains, Focşani, Galați, and the lower reaches of the Danube river.
On the following day the 2nd Ukrainian Front’s spearhead across the Siret river took Focşani After a brief and fruitless attempt to hold the line between Focşani and Galați with rear-echelon troops, the headquarters of the 6th Army fell back toward Buzău. Intermittent and fragmentary radio messages from the army’s encircled divisions suggested that two pockets had been created, the larger of 10 divisions stationary on the eastern bank of the Prut river to the east of Huşi, and the smaller of eight divisions moving slowly to the west in the area to the south of Huşi.
On the same day, to the north of Bucharest Romanian forces had surrounded the German force ordered to overthrow the coup in the Romanian capital. At Ploieşti Generalmajor Julius Kuderna’s 5th Flakdivision had lost the oil refineries and half of the town. Falling back from the Siret river, the 8th Army had under command barely enough troops to organise blocking detachments in the Oitoz pass between the Carpathian mountains and the Transylvanian Alps, and the passes farther to the north. The mountains themselves offered a measure of defensive support, but the deep German flank, 190 miles (305 km) long in the Transylvanian Alps from the south-eastern tip of Hungary to the Iron Gate, was wholly exposed. The aircraft of Luftflotte IV had to use the last of the fuel available to them to fly to bases in eastern Hungary. In the south the Bulgarians, not officially at war with the USSR and seeking anything which would keep Soviet forces out of Bulgarian territory, were disarming and interning all Heeresgruppe 'Südukraine' personnel who crossed the border.
By 29 September the Soviets' personnel casualties were 13,197 men killed or missing and 53,933 men wounded, and their matériel losses 75 tanks and self-propelled guns, 108 guns and mortars, and 111 aircraft. These were minuscule by comparison with the forces involved (1.341 million personnel and 1,874 tanks and assault guns, as well as 16,000 pieces of artillery and mortars, and 2,200 aircraft).
The Germans had lost up to 215,000 men (about 100,000 men killed and 115,00 men taken prisoner) as well as an unknown number of men wounded, 83 tanks and self-propelled guns, 3,500 guns, 3,300 motor vehicles and 330 aircraft from about 500,000 German troops, 405,000 Romanian troops, 170 tanks and 800 aircraft. The Romanian losses were 8,305 men killed, 24,990 men wounded and 170,000 men missing or taken prisoner, as well as 25 aircraft and unknown numbers of armoured fighting vehicles and pieces of artillery.
The scale of the German catastrophe is revealed by the fact that formations completely or largely destroyed included, from the 6th Army, the IV Corps, VII Corps, XXX Corps, XLIX Corps and LII Corps, the 13th Panzerdivision, 9th Division, 15th Division, 62nd Division, 76th Division, 79th Division, 106th Division, 161st Division, 257th Division, 258th Division, 282nd Division, 294th Division, 302nd Division, 306th Division, 320th Division, 335th Division, 370th Division, 376th Division and 385th Division, and 153rd Feldausbildungsdivision; from the 8th Army the 10th Panzergrenadierdivision; and from Luftflotte IV the 5th Flakdivision.
During the night of 29 August the Oberkommando des Heeres ordered Heeresgruppe 'Südukraine' to develop a southward-facing solid front along the east/west spine of the Transylvanian Alps and the south-east/north-west elevations of the Carpathian mountain connecting with von Weichs’s Heeresgruppe 'F' at the Iron Gate on the Danube river in the south and Heeresgruppe 'Nordukraine' along the Polish border in the north. Vezérezredes Lajos Veres von Dalnoki’s Hungarian 2nd Army, which was currently forming in eastern Hungary, was now placed under Friessner’s command. Forming a horseshoe shape with its closed end facing to the south-east, the mountains in fact afforded the the Germans and now the Hungarians the best line of defence against Soviet advances into north-west Romania and eastern Hungary, but only if Friessner could group together the strength sufficient to take and hold the passes on Romanian territory in the Transylvanian Alps. The difficulty of this task became clear on the following day, when Friessner reported that not a single division of the 6th Army had managed to escape. The remnants of this army, namely its headquarters and service troops with some 5,000 vehicles, were crammed into the Buzaul river valley and still under threat from the Soviet forces.
Thus Heeresgruppe 'Südukraine' was left with just four complete divisions: of these, three had been on the army group’s left flank and had not come under attack in the '2nd Iassy-Kishinev Strategic Offensive Operation', and one had been on its way out of the army group’s area and was returned only after the offensive had begun. All the army group now held was an intermittent front in the Carpathian mountains. If the Soviets decided to make a fast thrust to the north through the Predeal and Turnu Roșu passes, there was little hope for the German survivors of the '2nd Iassy-Kishinev Strategic Offensive Operation' proper.
On 30 August Malinovsky’s 2nd Ukrainian Front took Ploieşti, and on the following day entered Bucharest. On 29 August Malinovsky, in obedience to Stavka instructions, had divided his strength. Kravchenko’s 6th Tank Army, Trofimenko’s 27th Army and Managarov’s 53rd Army were despatched between the Danube river and the Carpathian mountains to clear southern Romania as far as Turnu Severin on the Danube river below the Iron gate. What was left was despatched to drive the Germans out of the eastern part of the Carpathian mountains: General Leytenant Filipp F. Zhmachenko’s 40th Army moved against the left flank of the still relatively intact 8th Army, and Shumilov’s 7th Guards Army and Gorshkov’s Cavalry-Mechanised Group 'Gorshkov' were to force the Oitoz pass and drive across the mountains toward Sibiu and Cluj.
As the Soviet forces started to wheel the axis of their advance from the south to the west in the area to the south of the Transylvanian Alps, Friessner decided he might sill be able to close at least the Predeal and Turnu Roșu passes. (von Weichs’s formations had assumed responsibility for the Iron Gate.) The remaining pass across the western end of the Transylvanian Alps was the Vulcan pass, and for the moment this was out of reach of both von Weichs’s Heeresgruppe 'F' and Friessner’s Heeresgruppe 'Südukraine'. Believing that his chances of securing and holding the passes to be slight, at his time Friessner ordered hos formations to reconnoitre a line on the Mureșul river across the western end of the Szekler strip.
On 5 September the Hungarian 2nd Army attacked to the south from the area of Cluj with the objective of closing the Turnu Roșu pass. During the previous day, aerial reconnaissance had detected signs that the 2nd Ukrainian Front was beginning to turn to the north, and Friessner had alerted his formations to prepare themselves, if ordered, to act rapidly and fall back behind the Mureșul river in a single bound, but in the short term the order did not have to be given. The Hungarian 2nd Army gained ground rapidly against feeble resistance by the hastily reconstituted Romanian 4th Army which, with the Romanian 1st Army, had been taken under Malinovsky’s command on 6 September.
During the day the 6th Army extracted its last men from the Buzaul river valley, but that and the Hungarian success were only minor successes in a generally unsuccessful day. After hearing nothing for several days, Friessner had no option but to concede the total loss of the five corps staffs and 18 divisions in the two pockets south of the Dniestr river’s southern reaches. On the same day, advancing to the west, the Soviets reached Turnu Severin, just 10 miles (16 km) to the south-east of the Iron Gate. By the evening Friessner had decided that he would have to pull the 6th Army and 8th Army back behind the Mureșul river, but decided not to do so for a short time longer so that there would be no morale-sapping contrast between German troops retreating and Hungarian troops advancing.
The Hungarian 2nd Army advanced again on 6 September, but more slowly than it had on the previous day. The 6th Army, which had taken command of the 8th Army's right-flank corps, reported that the Soviets had reached Oitoz pass and, off the southern end of the army’s front, had already traversed the Predeal pass and were grouping at Brașov. Friessner therefore authorised the army to start pulling back during the night if the pressure on it became too great. Friessner informed Guderian that the Hungarians could not be expected to reach the Turnu Roșu pass as the Romanians had requested Soviet support. Friessner had communicated with the Hungarians, and the decision had been made for both the Germans and the Hungarians to fall back to a shorter line.
On the following day the Hungarian offensive ended. The effect of this offensive’s two successful days could be observed farther to the south. Kravchenko’s 6th Tank Army, to become the 6th Guards Tank Army very shortly and which had been advancing toward the Iron Gate, had now halted and wheeled to the north. One of its two mobile corps (General Leytenant Vasili M. Alekseyev’s V Guards Tank Corps and General Major Boris M. Skvortsov’s V Guards Mechanised Corps) was crossing the Turnu Roșu pass, and the other was heading into the Vulcan pass. By 12.00 the leading units were through the Turnu Roșu pass and reached Sibiu, 40 miles (64 km) from the Hungarian frontier. It was at this point that Friessner decided to halt the Hungarian 2nd Army, take it into a defensive line, and support it with all the German anti-tank weapons which could be found. Orders went out to the 6th Army and 8th Army to start their withdrawal during the same night. As this was happening, the operations branch of the Oberkommando des Heeres attempted to halt the withdrawal with an order from Hitler. When Friessner answered that the withdrawal had already started, he was informed that Hitler 'had taken notice' of the withdrawal to the first phase line but reserved all subsequent decisions to himself.
Five days earlier Hitler had personally ordered Friessner to prepare a withdrawal of some 40 miles (64 km) farther to the west than the proposed line on the Mureșul river, but had since changed his mind as he was determined to hold onto Hungary, Germany’s last ally, and as he was arriving at a new and novel estimate of Soviet strategy. The first of these two reasons was the more immediate. Since Romania’s change of allegiance, Hungary, which had never been wholly reliable German ally, had fallen into a state of acute internal political tension. Vezérfökapitány Miklós Horthy de Nagybánya, the regent of Hungary, had dissolved all political parties and declared his loyalty to Germany. His first impulse was apparently to seize the opportunity for the annexation of the Romanian parts of Transylvania, an action with which Hitler was happy to agree after the Romanian change of allegiance. But by 24 August the internal condition of Hungary appeared so uncertain that the Oberkommando der Wehrmacht moved two Waffen-SS divisions close to Budapest, the capital of Hungary, to be on the spot to put down any anti-German coup.
The events of the next few days were reassuring, however, at least on the superficial level. In particular, the Hungarian armed forces, appearing to be loyal to the alliance, set about mobilising their forces for a war against their ancient enemy Romania with what was, under the circumstances, surprising energy. The appointment on 30 August of Vezérezredes Géza Lakatos as minister president to replace Vezérezredes Döme Sztójay, who was ill, and the appointments to his cabinet preserved the hold inside the Hungarian government which the Germans had established in the spring. On the other hand Horthy kept out representatives of the radical rightist, fanatically pro-German Arrow Cross Party.
The first overt alarm was raised on 7 September when, in a flash of panic touched off by a false report that Soviet forces had reached Arad on the undefended southern border only 140 miles (225 km) from Budapest, the Hungarian Crown Council met in secret and later, through the chief-of-staff, presented an ultimatum to the Oberkommando des Heeres to the effect that unless Germany sent five Panzer divisions within 24 hours, Hungary would reserve the right to act as its interests might require. Guderian called this extortion, but gave his word to defend Hungary as if it were part of Germany and announced that he would send one Panzer corps headquarters and one Panzer division, later adding two Panzer brigades and two SS divisions, bringing the total to approximately the five divisions demanded by Hungary. Because Hungary was in so parlous and nervous a condition, Hitler refused to sacrifice the Szekler strip even though Friessner and the German military plenipotentiary in Budapest assured him that the Hungarians were reconciled to losing the territory.
On 9 September Friessner travelled to Budapest and persuaded Horthy to put his agreement to the withdrawal in writing. The impressions he received from talking to Horthy, Lakatos and the Hungarian military leadership were so disturbing that Friessner decided to report on them to Hitler in person on the next day. At Hitler''s headquarters Friessner learned the second reason why Hitler did not want to give up the Szekler strip: he had come to the conclusion that having broken into the Balkans (Tolbukhin, promoted on 12 September to Marshal Sovetskogo Soyuza, had driven his 3rd Ukrainian Front across the Romanian/Bulgarian border on 8 September), the USSR would now put its old ambition of political hegemony in south-eastern Europe and control of the Dardanelles ahead of the drive toward Germany. This would infringe on British interests, and the war would therefore turn in Germany’s favour because the UK would realise that it needed Germany as a buffer against the USSR.
As the withdrawal had already started, Hitler agreed by the end of the interview to let the army group fall back as far as the Mureșul river, but that the line be adjusted to include the strategically important manganese mines at Vatra Dornei and that this line was to be held though the oncoming winter months. Hitler also decided, after hearing Friessner’s report, to 'invite' the Hungarian chief-of-staff for a discussion on the following day.
On 10 September, in Budapest, Horthy conferred with a select group of prominent politicians, and a day later informed the cabinet that he was about to ask for an armistice and wished to know which of its members were willing to share the responsibility for that step. The vote went heavily against Horthy, and the cabinet then demanded his resignation. Horthy refused.
When the Hungarian chief-of-staff travelled to Hitler’s headquarters on 12 September, he went as an ally. The day’s delay had aroused Hitler’s suspicions, however, and he told the Hungarian military attaché that he had lost all confidence in the Hungarian government. The chief-of-staff’s visit therefore proceed along much the same lines as that of Antonescu in August, with mutual complaints and recriminations which were finally obscured by a veil of effectively empty promises.
Thus was set the scene for the Soviet 'East Carpathian Strategic Offensive Operation', which had in fact started on 8 September.