The 'Ostrogozhsk-Rossosh Offensive Operation' was a Soviet undertaking by the Voronezh Front against the Hungarian 2^nd Army and parts of the Italian 8^th Army as the first of the six sub-operations together constituting the 'Voronezh-Kharkov Strategic Offensive Operation' (13/27 January 1943).

The offensive is better known as a successor to the 'Middle Don Offensive Operation', otherwise 'Maly Saturn', undertaken in the period in which Generaloberst Friedrich Paulus’s 6^th Army had been encircled in Stalingrad and was on the verge of total destruction.

The third stage of the great counter-offensive which culminated in the destruction of the 6^th Army and the German evacuation of the Caucasus was the offensive made by General Polkovnik Filipp I. Golikov’s Voronezh Front on Generaloberst Hans von Salmuth’s German 2^nd Army and Vezérezredes Gusztáv Jány’s Hungarian 2^nd Army, with Kharkov and the Donets basin as the Soviet forces' immediate objectives. The assault frontage stretched more than 300 miles (480 km) from Livny to Kantemirovka, and Golikov was to be assisted by the flanking formations of General Polkovnik Maks A. Reiter’s Bryansk Front to the north and General Nikolai F. Vatutin’s South-West Front to the south. The main blows were to be struck by General Leytenant Kirill S. Moskalenko’s 40^th Army together with the XVIII Separate Corps against the Hungarians on the right, and General Leytenant Pavel S. Rybalko’s 3^rd Tank Army against the Italians on the left to encircle the Hungarian 2^nd Army by means of a double envelopment, the two pincers meeting about 50 miles (80 km) to the rear near the town of Alexeyevka. The Soviet forces were then to turn outward and roll up the German 2^nd Army to the north and Generale d’Armata Italo Gariboldi’s Italian 8a Armata to the south by attacking their exposed flanks in conjunction with General Major Nikandr Ye. Chibisov’s 38^th Army and General Major Ivan D. Chernyakhovsky’s 60^th Army of the Voronezh Front, General Major Nikolai P. Pukhov’s 13^th Army of the Bryansk Front and General Leytenant Fyedor M. Kharitonov’s 6^th Army of the South-West Front.

In this main assault sector, the German 2^nd Army had two corps with seven divisions; the Hungarian 2^nd Army comprised only nine brigades or light divisions, one armoured division and one German infantry division; and the Italians fielded one alpine corps of three divisions. The Axis forces were outnumbered by the Soviet forces in both armour and artillery, the Voronezh Front alone consisting of 15 infantry divisions, six infantry brigades, two tank corps and eight tank brigades, and a number of cavalry units.

Golikov was allowed three weeks for reconnaissance and preparation: the reconnaissance effort was carried in part from the air, and in part from special observation and command posts constructed close to the Hungarian positions. Ground reconnaissance by probing attacks and fighting patrols was discouraged lest the Axis forces be alerted. It soon became apparent that the Hungarian defences consisted of two defensive zones, one about 4 miles (6.5 km) deep and a second about 10 to 12 miles (16 to 19 km) farther to the rear. As a result of the Hungarian forces' relative passivity, the Soviets were able to withdraw almost entirely from all secondary sectors, which made possible the concentration of about 200 pieces of artillery and mortars per mile on each of the main assault frontages. Guns of all calibres were sited as direct-fire weapons for the destruction of the many strongpoints which had been identified. The lack of cover on the open steppe made it necessary for the Soviets to bring troops forward over the last 100 miles (160 km) to the front only by night.

It seems clear that the Hungarian forces believed that the Soviets had expended their strength and for this reason that an attack was unlikely. On 7 January, only seven days before the scheduled start of the offensive, Vezérõrnagy Gyula Kovács, the Hungarian 2^nd Army's chief-of-staff, sent to Budapest a report in which he discounted the possibility of any Soviet attack on his sector, but in fact an attack in this sector was not unexpected by the Germans.

Although the main attack was not due until 14 January, a preliminary reconnaissance probe made in some strength on 12 January threw the Axis forces into such disarray that Soviet troops were able to make an indentation, some 3.1 miles (5 km) deep, into the Hungarian defences. The main offensive was then launched without further delay, tank-mounted mine rollers being used for the first time to breach the defender’s minefields. Soviet accounts claim that the preparatory bombardment and the use of guns in the direct-fire role was so effective that the Hungarian artillery observation posts were destroyed within the first few minutes, and the Soviet armour and infantry formations then broke through almost without loss.

By 15 January the field defences which the Axis forces had held for a year, but had failed to develop significantly, were penetrated despite the delivery of repeated counterattacks by Ezredes Ferenc Bisza’s Hungarian 2^nd Armoured Division. On the following day, the Hungarian communication system broke down and the defence became totally disjointed. By 18 January Rybalko’s 3^rd Tank Army and Moskalenko’s 40^th Army had met near Alexeyevka. and most of the Hungarian 2^nd Army, part of the Italian alpine corps, and elements of Generalleutnant Arno Jahr’s (from 20 January General Karl Eibl’s and from 21 Januar Generalleutnant Otto Heidkämper’s) XXIV Panzerkorps and Generalmajor Hans Cramer’s Generalkommando zbV 'Cramer' had been surrounded. (The XXIV Panzerkorps was under Gariboldi’s command and comprised one German Panzer division and two infantry divisions. Gariboldi also had under command of his 8a Armata two other German formations. On 14 January General Martin Wandel, then commander of the XXIV Panzerkorps, went missing and was never seen again. He was succeeded by Jahr, who committed suicide on 20 January, then by Eibl, who was killed in a 'friendly fire' incident by Italian troops only one day later, and then by Heidkämper. The Generalkommando zbV 'Cramer' comprised one German infantry division and part of the Hungarian armoured division, together with other German elements.)

The weather conditions at this time were acutely wintry, and in the heavy snow storms many of the encircled troops escaped, but by 27 January the Soviets could claim the capture of 86,000 prisoners, most of them Hungarians. The southern flank of von Salmuth’s German 2^nd Army was now totally exposed, and on 28 January Moskalenko’s 40^th Army moved to the north on Kastornoye across the German line of communications to meet Pukhov’s 13^th Army of the Bryansk Front. Two corps of the German 2^nd Army, totalling about seven divisions, were cut off, Adolf Hitler having already shown his typical reluctance to allow this army to evacuate Voronezh and withdraw. For these troops, however, there was to be no repetition of Stalingrad. Voronezh was abandoned and set on fire and the many pockets of encircled troops fell back to the west in a fighting retreat, most of them surviving the 120-mile (195 km) march to Rylsk in temperatures of -25° C (-13° F) before they reached the relative safety of the new German line. Their heavy equipment had been lost or abandoned in almost its entirety.

On 21 January Generaloberst Maximilian Freiherr von Weichs reported an intensely difficult situation to Hitler: there was now a 200-mile (320-km) gap in the German front where his Heeresgruppe 'B' had formerly, and he held out little hope of stopping the Soviet forces, especially as the latter’s formations had changed their tactics and now simply bypassed all the Axis strongpoints. He feared for the continued survivability of the German 2^nd Army, and could see that the Soviets might be planning to drive to the south-west through the gap, thereby cutting off the withdrawal of Generalfeldmarschall Erich von Manstein’s Heeresgruppe 'Don'. No German reserves were available with the exception of one infantry division being transferred from Generalfeldmarschall Günther von Kluge’s Heeresgruppe 'Mitte' and SS-Oberstgruppenführer und General der Waffen-SS Paul Hausser’s II SS Panzerkorps which was still arriving from western Europe. von Kluge, whose army group had been under intense Soviet pressure from the Kalinin Front and West Front right through the winter of 1942/43 and now highly concerned of its danger should the Soviet penetration wheel to the north, urged in strong but wholly unsuccessful terms for authorisation to evacuate the great salient near Rzhev and so create reserves to deal with the threat.

Marshal Sovetskogo Soyuza Georgi K. Zhukov and Marshal Sovetskogo Soyuza Aleksandr M. Vasilevsky had been attached for a short time during a time late in January to the Voronezh Front to recommend the course of further operations and, following Zhukov’s recommendations, a new 'Kharkov Offensive Operation', otherwise known as 'Zvezda', was planned for the liberation of the Kharkov area. It is possible that the Stavka had some reservations as the plan involved a thrust by Golikov’s forces in two divergent directions at the same time, toward Kursk and Kharkov. 'Zvezda' began on 1 February and the Soviet forces, not slow in exploiting their advantage, pushed through the gap, Golikov’s Voronezh Front moving almost straight to the ward toward Kursk and Kharkov, while Kharitonov’s 6^th Army and General Leytenant Vasili I. Kuznetsov’s 1^st Guards Army of Vatutin’s South-West Front were directed towards Mariupol on the Sea of Azov, in order to cut the communications of both von Manstein’s Heeresgruppe 'Don' and von Kleist’s Heeresgruppe 'A' that was still in the Caucasus.