'Mars III' was the Axis movement of Hungarian reinforcements for the Axis 'Blau' summer offensives of 1942 Generalfeldmarschall Fedor von Bock’s Heeresgruppe 'Süd' on the Eastern Front (spring 1942).

These reinforcements took the form of Altábornagy Gusztáv Jány’s 2^nd Army of some 209,000 men, and by 11 April this formation had come under the command of von Bock’s Heeresgruppe 'Süd' in the southern USSR and then, from July, of Generaloberst Maximilian Reichsfreiherr von Weichs’s Heeresgruppe 'B' in 'Blau I'. In June and July the 2^nd Army was involved in the Battle of Voronezh and, operating in and around Voronezh on the Don river, supported Generaloberst Hermann Hoth’s 4^th Panzerarmee. Though technically an Axis success, this pyrrhic victory fatally delayed the arrival of the 4^th Panzerarmee in the Caucasus, farther to the south, to support Generalfeldmarschall Wilhelm List’s Heeresgruppe 'A'.

The 2^nd Army is the best known Hungarian army of World War II as a result of its involvement in the Battle of Stalingrad. But before being moved to the USSR, the majority of the army’s strength had received just eight weeks of training, and the only tactical experience possessed by many of the men was a series of manoeuvres just before the army’s movement to the Eastern Front.

On arrival, the 2^nd Army was given the task of protecting the northern flank of Generale d’Armata Italo Garibaldi’s Italian 8a Armata between Novaya Pokrovka on the Don river and Rossosh, thereby freeing Generaloberst Friedrich Paulus’s German 6^th Army to continue its attack on Stalingrad.

Like most of the formations shielding the flanks of the 6^th Army, the 2^nd Army was destroyed as the Soviets launched 'Uran' and 'Malyi Saturn'. As part of these operations, two Soviet pincers drove through General de armatâ Petre Dumitrescu’s Romanian 3^rd Army to the north of Stalingrad and General de corp de armatâ Constantin Constantinescu-Clap’s Romanian 4^th Army to this city’s south, thereby trapping Paulus’s 6^th Army in the area of Stalingrad. On 12 December, the Germans responded with 'Wintergewitter' (i) to relieve the 6^th Army by cutting through the south-western quadrant of the Soviet encirclement resulting from 'Uran'. The Soviets counterattacked on 16 December in 'Malyi Saturn', smashing through the junction of the Italian 8^th Army and the Hungarian 2^nd Army in the area held by Generale di Corpo d’Armata Gabriele Nasci’s Italian Corpo d’Armata Alpino (Generale di Divisione Luigi Reverberi’s 2a Divisione alpina 'Tridentina', Generale di Divisione Umberto Ricagno’s 3a Divisione alpina 'Julia', and Generale di Divisione Emilio Battisti’s 4a Divisione alpina 'Cuneense') and threatening the flank of German forces attempting to relieve the 6^th Army by cutting off the attempted relief force along the Donets river.

On 13 January 1943 Soviet forces in overwhelming numbers began the 'Voronezh-Kharkov Strategic Offensive Operation', otherwise known as 'Skachok', simultaneously along the fronts of the Bryansk, Voronezh and South-West Fronts, and the forces of the Voronezh Front rapidly destroyed the Hungarian 2^nd Army near Svoboda on the Don river. The offensive farther to the north on Generaloberst Hans von Salmuth’s German 2^nd Army threatened to encircle that formation as well, though it managed to extricate itself and retreat. By 5 February troops of the Voronezh Front were approaching Kharkov.

During its year on the Eastern Front the Hungarian 2^nd Army took enormous losses. Of an initial force of about 200,000 Hungarian soldiers and 50,000 Jewish forced labourers, some 100,000 had died, 35,000 had been wounded and 60,000 had been taken prisoner. Only about 40,000 men returned to Hungary.