The German losses sustained in the first year of warfare led to a less ambitious series of objectives being specified for the second summer campaign. Hitler's focus was on gaining control of the resources in the Caucasus. After the campaign was underway, the city of Stalingrad on the Volga became another objective. The extended left flank was eventually defended by relatively weak German allied armed forces from Romania, Hungary and Italy.
By mid-August 1942, German armored forces were pressing the Soviet armies defending the front before Stalingrad into the city itself. Panzers attached to 6th Army pushed east in conjunction with 4th Panzer Army striking northward.
As German armed forces pressed forward into the city of Stalingrad during September, they encountered increasingly effective resistance from the defending Soviet troops. Within Stalingrad, various complexes became battlegrounds
As the German 6th Army continued its battle of attrition to capture Stalingrad, the Soviet military command prepared to launch a counteroffensive (Operation Uranus) that aimed to encircle the German army fighting in Stalingrad and bring about the collapse of southern wing of the German front.
German armed forces of Army Group Don made an unsuccessful attempt break through and relieve the German 6th Army encircled in Stalingrad. Soviet military resistance proved too great to overcome with the German units available and the German 6th Army remained isolated.
By the time the German 6th Army surrendered at Stalingrad, the Red Army aggressively pursued the remnants of Army Group Don, now renamed Army Group South, further west. Soviet units recaptured Kharkov and were approaching the Dniepr River. However, the commander of Army Group South, F.M. von Manstein marshaled forces for a counterattack in March 1943 that stabilized the southern wing of the Eastern Front until the Battle of Kursk in July 1943.