The 'Mius River Offensive Operation' was a Soviet undertaking, partnered to the north by the 'Izyum-Barvenkovo Offensive Operation', by the South Front to clear the German 6^th Army of Heeresgruppe 'Süd' from the Donbas area to the west of the Mius river (17 July/2 August 1943).

The plan created by the Soviet high command ordained that as soon as the Battle of Kursk unfolded in the German 'Zitadelle' offensive, several neighbouring fronts would go over to the offensive so that the Germans would not able able to siphon troops from these areas to reinforce those round the Kursk salient. The South-West Front was to launch an offensive toward Barvenkovo, the South Front was to attack from the Matveyev Kurgan region to the west in the direction of Stalino and farther to Melitopol in the 'Mius River Offensive Operation', the Bryansk Front was to drive on Orel, and the West Front was to advance toward Karachev. The whole Soviet concept was based on the desire to deprive the Germans of the opportunity to manoeuvre their reserves.

In 1942 the Germans began to construct a defensive line, known as the 'Mius-Linie' , on the eastern approaches to the strategically important Donbas area through the regions centred on Rostov-na-Donu, Voroshilovgrad and Donetsk. Along this line the Germans halted the Soviet offensive during the 'Donbas-Mariupol Offensive Operation' in February 1943, and after this the fortifications were steadily and continuously improved and completed. By July 1943, the 'Mius-Linie' comprised a trio of defensive lines. The first lay on the western bank of the Mius river and extended to a depth of 13 miles (21 km). The second extended along the banks of the Mokry Elanchik and Krynka rivers, and extended to a depth of 9.5 miles (11 km). The third was situated along the Kalmius and Gruz’ka rivers and extended to a depth of 4.35 miles (7 km). Each defensive zone was based on as many as three lines of trenches, between which there were intermediate and cut-off defensive lines. The total length of all trenches in the 'Mius-Linie' system exceeded 11,185 miles (18,000 km). Between them were minefields with a density of up to 4,675 mines per 0.385 miles² (1,800 mines per km²). For each 0.61 miles (1 km) of front there were between 12 and 15 pillboxes and bunkers, most of these being constructed of reinforced concrete. The area was also strewn with 'wolf pits' whose bottoms were h was stuck with sharpened stakes, and other features were anti-tank ditches and mobile armoured shields with firing embrasures. The total depth of the German defences was between 25 and 31 miles (40 and 50 km).

The defence of the 'Mius-Linie' in the zone of the forthcoming Soviet offensive was the responsibility of General Karl-Adolf Hollidt’s 6^th Army of Generalfeldmarschall Erich von Manstein’s Heeresgruppe 'Süd', with the air support of major elements of Generalfeldmarschall Wolfram Freiherr von Richthofen’s Luftflotte IV. Three corps of the 6^th Army, which together controlled 11 divisions and five battalions of assault guns, held the 110-mile 180-km) front threatened directly by the forces of the South Front, and the German Donbas grouping also included Generaloberst Eberhard von Mackensen’s st Panzerarmee.

The Soviet high command allocated to General Polkovnik Fyedor I. Tolbukhin’s South Front the task of pinning and then, under favourable conditions and in co-operation with the South-West Front, defeating the German forces in the Donbas group so so preventing the redeployment of any of its strength northward to the Kursk salient where the decisive battles of 'Zitadelle' were taking place.

The main forces of the South Front were General Leytenant Georgi F. Zakharov’s (from 30 July General Leytenant Yakov G. Kreizer’s) 51^st Army, General Leytenant Vyacheslav D. Tsvetsayev’s 5^th Shock Army, General Leytenant Vasili F. Gerasimenko’s 28^th Army, General Leytenant Vasili A. Khomenko’s 44^th Army and Kreizer’s (from 30 July Zakharov’s) 2^nd Guards Army. Air support was the task of General Leytenant Timofei T. Khryukin’s 8^th Air Army.

By the beginning of the 'Mius River Offensive Operation', the Soviet front-line strength was 271,790 men. The primary blow was delivered by the 5^th Shock Army and 28^th Army in the centre from the area of Kuybyshevo and Dmitrovka in the direction of Uspenskaya, Artyomovka and Fedorovka. Should the operation proceed as favourably as the Soviets expected, these armies were then to advance through Amvrosievka and outflank the German forces in the Taganrog area from the north. To develop success the Soviets had concentrated a powerful reserve in the form of the 2^nd Guards Army, which was based on two mechanised corps (the II Guards Mechanised Corps and the IV Mechanised Corps ). The 2^nd Guards Army was to enter the fray on the 28^th Army’s sector. Supporting attacks were to be made to the north of the main assault by the 51^st Army in the direction of Krasny Luch and Stalino, and to the south of the main assault by the 44^th Army in the area to the north of Matveyev Kurgan.

As noted above, the 'Izyum-Barvenkovo ​Offensive Operation' was to be carried out by the South-West Front with similar objectives goals, and the operations of the South Front and South-West Front were co-ordinated by the Stavka representative, Marshal Sovetskogo Soyuza Aleksandr M. Vasilevsky, the chief of the Soviet army’s general staff.

According to von Manstein, German aerial reconnaissance provided good information on the Soviet preparations for the forthcoming offensive and this allowed the Germans to optimise their defence arrangements.

The 'Mius River Offensive Operation' began on 17 July with a powerful artillery barrage. From its first jours the battle became very hard fought, all the more so as many of the German strongpoints and field fortifications were not suppressed by the Soviet artillery. German troops put up their typical stubborn resistance. In addition, the Germans immediately committed major air strength into the battle, and German warplanes thus effectively bombed the advancing troops and the echeloned reserves approaching the battlefield. The terrain conditions also militated against Soviet success: the western bank of the Mius river dominated the eastern bank, and numerous the presence of many small river and streams made it difficult for the Soviets to use their armour.

Nevertheless, in the area of the primary assault, the South Front’s troops managed to penetrate the German defences, breaking through the first defensive line and seizing a small bridgehead some 21.75 miles (35 km) wide and between 3.1 and 3.7 miles (5 and 6 km) deep across the Mius river in the area of Stepanovka and Marinovka. However, fighting with determination and making maximum use of their powerful defence system, the Germans then brought the Soviet offensive to a halt. In the days which followed, exceptionally violent fighting took place along the Soviet bridgehead: Soviet troops delivered continuous attacks on the Germans, whose front-line formations and units repulsed the Soviet attacks and themselves made counterattack after counterattack. Reinforcements were also deployed into the breakthrough area. By 19 July the Germans had brought into the battle four divisions from the army reserve: these were Generalleutnant Gerhard Graf von Schwerin[s 16^th Panzergrenadierdivision, Generalleutnant Alfred Thielmann’s 32^nd Division, Generalleutnant Hermann Recknagel’s 111^th Division and Generalleutnant Walther Lucht’s (from 22 July Generalmajor Wilhelm Kunze’s) 336^th Division. Also committed were the men of the non-commissioned officer school of the 6^th Army, and between 20 and 24 July the XXIV Panzerkorps from the 1^st Panzerarmee. Several aviation groups were urgently transferred from the Kursk front, and a significant quantity of German artillery was transferred from sectors of the front that were not currently under attack.

The Soviet command also introduced a front-line reserve: during the afternoon of 17 July the bridgehead saw the arrival of the 2^nd Guards Army began. It was as a result of the stalling of the 28^th Army’s offensive that Tolbukhin had decided to bring in Tsvetayev’s 5^th Shock Army. The arrival and commitment of the 2^nd Guards Army with its mechanised corps was planned and executed poorly, however, and the new forces were attacked from the air and by artillery as they approached and attempted to cross the Mius river. Thus the planned revival of the Soviet offensive failed as the fresh forces became struck in the German defences after managing to advance only a short distance and liberating just three villages.

By 19 July, the Germans were counterattacking the Soviet bridgehead from the south with the 16^th Panzergrenadierdivision and Generalleutnant Nikolaus von Vormann’s 23^rd Panzerdivision. This attack was driven back, however, and a fresh counterattack on the following day was also repelled, but the Germans nevertheless managed to pin the advancing Soviet troops. In these battles, the Germans lost as many as 100 tanks and assault guns.

Only on 21 July, as a result of difficulties in crossing the Mius river and concentrating in the bridgehead, were the Soviets able to commit the IV Mechanised Corps, which had already suffered significant losses from German air attacks. On 22 July, Soviet troops resumed their offensive and advanced a short distance farther, but could not break through the German defences. On 23 July the revived Soviet offensive was halted by the Germans, and the final Soviet attempt on 25 July ended without any results at all and with significant losses.

To prevent a breakthrough of the defences on the Mius river, on 28 July SS-Oberstgruppenführer Paul Hausser’s II SS Panzerkorps (SS-Gruppenführer Max Simon’s SS Panzergrenadierdivision 'Totenkopf', SS-Obergruppenführer Walter Krüger’s SS Panzergrenadierdivision 'Das Reich' and Generalleutnant Franz Westhoven’s 3^rd Panzerdivision) was transferred to the bridgehead area from the area of the Kursk salient. General Werner Kempf’s Armeeabteilung 'Kempf' and four air groups from near Kursk and from the Taman peninsula were also added to the German strength.

On 30 July the reinforced German forces launched a strong counter-offensive with as many as 258 tanks and about 100 assault guns against the 5^th Shock Army’s XXXI Corps and neighbouring elements of the 28^th Army, which had been greatly weakened in the earlier fighting. The German effort was supplemented by Generalleutnant Johannes Block’s 294^th Division and Generalleutnant Willibald Spang’s 15^th Luftwaffe Felddivision attacked units of the 2^nd Shock Army. The XXIV Panzerkorps' advancing formations and units squeezed the the Soviet forces into a decreasing area, and four Soviet infantry regiments were surrounded. The II SS Panzerkorps made a small penetration into the Soviet defences in only one sector, but in all other areas the corps' attacks were driven back with heavy losses (91 tanks and more than 900 men). Fighting continued at a high intensity throughout the night and the following day as each side continually counterattacked the other, and positions, heights and settlements were repeatedly taken and lost. Even so, there remained the very real threat of the XXIV Panzerkorps' recapture of the bridgehead and the encirclement of the Soviet troops within it.

At Iosif Stalin’s demand on 31 July, the Soviets expended great effort in their attempt to extract the four encircled regiments, but only one of them was saved. The men of the other three had been killed almost to as man. On 1 August, the German attacks continued without pause as they developed their advance. This was a slow process in the face of determined Soviet. The Germans committed almost all of their 400 to 500 combat-capable armoured vehicles in their efforts to maintain pressure on the Soviet forces, whose army commanders were compelled, on their own initiative, to begin a partial withdrawal of their troops behind the Mius river once more. Appreciating the impossibility of restoring positions and in order to prevent the destruction of the troops in the bridgehead, during the evening of 1 August Tolbukhin requested the authority to withdraw the troops remaining in the bridgehead back behind Mius river. This permission was granted, and the main force’s evacuation was effected in difficult conditions, covered by reinforced rearguards, during the night of 1/2 August, and by 17.00 on 2 August the rearguards had also crossed.

On the auxiliary axes, the Soviet offensive was repulsed: in the north the 51^st Army advanced a short distance on 17 July before being driven back to its original position by a German counterattack on 20 July 20. Subsequent attacks up to 27 July 27 were unsuccessful. In the south the 44^th Army’s effort ended in the same way.

The 'Izyum-Barvenkovo Offensive Operation' by the neighbouring South-West Front ended in much the same way.

In the 'Mius River Offensive Operation', therefore, the Soviet were unable to break through the Mius river front and defeat the Germans. The bridgehead occupied at the beginning of the operation and held with heavy losses had to be abandoned. However, the second goal of the operation was achieved: the active operation of the South Front pinned the 6^th Army and the 1^st Panzerarmee in the Donbas area, thereby preventing them from redeploying any of their divisions to the area of Kursk. Moreover, the Germans had been compelled to send reserves from the area near Kharkov to the 6^th Army, as too were a large number of formations and units from other areas, including the II SS Panzerkorps from the Kursk area. This reversed the flow of German troop movements which had been planned before the Soviet offensive: for example, the 16^th Panzergrenadierdivision and the 23^rd Panzerdivision had already begun to move from the Mius front toward Kharkov before the start of the Soviet operation. This undoubtedly facilitated the success of the Soviet offensive in the 'Belgorod-Kharkov Offensive Operation'.

The total losses of the Soviets in the 'Mius Rover Offensive Operation' were 61,070 men, of whom 15,303 were killed, missing or taken prisoner, and 45,767 wounded or taken ill. In his memoirs, von Manstein claimed that in the battle for the Mius river bridgehead, Soviet troops lost about 18,000 men taken prisoner, as well as 700 tanks, 200 pieces of artillery and 400 anti-tank guns destroyed or disabled.

The 6^th Army recorded, for the period between 17 July and 2 August, the loss of 21,369 men, including 3,289 killed, 2,254 missing and 15,817 wounded. Losses in tanks and assault guns exceeded 300. The total German losses, according to the Soviets, were in the order of 35,000 men.

The chief reasons for the failure of the 'Mius River Offensive Operation' were mistakes made by the South Front, which seriously underestimated the strength of the German defence despite the fact that its command staff had an adequate understanding of the defence’s physical layout

The South Front’s mistakes included: firstly, a dispersal of its available strength through the use of one main and two subsidiary drives; secondly, its belated and poorly organised commitment of the 2^nd Guards Army; thirdly, Tolbukhin’s decision to resume the offensive in the shortest possible time without sufficient preparation; fourthly, the great problems associated with the simultaneous supply of three armies in a bridgehead that was under constant artillery fire, resulting in the troops' constant shortages of ammunition, food and fuel; fifthly, the hesitation of the Soviet command (including Stalin, after 30 July 30 with regard to the fate of the bridgehead until 1 August, when its loss became inevitable; sixthly, lack of adequate reconnaissance, and the inability of artillery and aviation during the initial artillery preparation to suppress the German artillery; seventhly, the German air superiority, which inflicted heavy losses on the Soviet ground forces, attacked advancing reserves and disrupted the supply of ammunition and other supplies; eighthly, poor communications between the front and its armies, and between the armies and their corps, which rendered it difficult to generate any rapid response to German counterattacks; and ninthly, the Germans' skilful concentration of troops and the redeployment of large formations from other sectors of the front.