On July 25, 1942, German Army Group A crossed the lower Don and then spread out and advanced south in a 120-mile front from the Sea of Azov to Zymlianskaya, meeting only light resistance from rear guards of the Soviet Southern Front. By this time, the Red Army had become wary from again being caught up in the Wehrmacht’s encirclement strategy that had annihilated many Soviet armies in the previous year.
In late July 1942, the Germans cut the rail line linking the Caucasus to central Russia, which so alarmed Stalin that he issued Order 227, which contained the famous “Not one step back!” command to Soviet forces to hold all current frontlines, and which later contributed to the outcome in the battle for Stalingrad.
(Taken from Invasion of the Soviet Union – Wars of the 20th Century – World War II in Europe: Vol. 6)
However, in southern Russia, German Army Group A made rapid progress, taking Salsk on July 31, Stavropol on August 5, and Maikop on August 9, by then reaching the northern foothills of the Caucasus Mountains, some 300 miles from its starting point in just two weeks. German commandos reached Grozny one day earlier, but were unable to prevent the retreating Red Army from destroying the oil installations, which German engineers later estimated would take one year to return to service. Mount Elbrus, the 18,000-foot highest peak of the Caucasus, also was reached, this “stunt” as Hitler called it so infuriating him that he threatened to court martial the commander of the German 1st Mountain Division who had authorized the climb.
By early September 1942, the German 11th and 17th Armies and Romanian 3rd Army, advancing along the Black Sea coast, had captured the Taman Peninsula and the Soviet naval bases there, including Novorossiyk, but attempts to advance further south to Tuapse met increasingly strong resistance. In the east, German 1st Panzer Army took Elista on August 13 and Mozdok on August 25. But operations aimed at Astrakhan in the east and Grozny and its oil fields in the south failed to make major progress. Nalchik was taken on October 28 and Alagir on November 5, marking the farthest German advances in the Caucasus.
All through its drive to the Caucasus, German Army Group A had experienced severe logistical difficulties from the rail and road supply systems, and sometimes were forced to abandon its equipment and resource-heavy tanks to continue the advance. The Luftwaffe often took on the responsibility of delivering much needed petroleum and supplies to the most advanced units. But German planes supporting the Caucasus campaign soon were redeployed in the increasingly fierce battle for Stalingrad. The Soviet Air Force brought in 800 bombers, and with the Luftwaffe withdrawing from the Caucasus, this allowed the Soviet planes to gain control of the sky. Furthermore, by November 1942, snow had began to fall and temperatures dropped, signaling the approach of winter, which practically ended the prospect of the Axis crossing the remaining 700-mile distance of the Caucasus to oil-rich Baku at the other end against Soviet forces that were dug in along the mountain passes.
By November 1942, Hitler conceded that the campaign to capture Baku could not be achieved before winter set in, and as he and the German High Command were by now fully engrossed in the Stalingrad battle, on November 22, he ordered German Army Group A to dig in and hold its lines. Earlier in October 1942, Hitler ordered the destruction of the Grozny and Baku oil facilities, that if he could not acquire them, then they should likewise be denied to the Soviets. The Grozny oil fields were destroyed by German air raids. However, Baku was not attacked, because of strong Soviet air defenses in its oil installations and because of the great distance involved, i.e. German bombers could only reach Baku using the most direct (and predictable) route, and thus were vulnerable to Soviet anti-aircraft fire.
Battle of Stalingrad Meanwhile to the north, German Army Group B, tasked with capturing Stalingrad and securing the Volga, began its advance to the Don River on July 23, 1942. The German advance was stalled by fierce resistance, as the delays of the previous weeks had allowed the Soviets to fortify their defenses. By then, the German intent was clear to Stalin and the Soviet High Command, which then reorganized Red Army forces in the Stalingrad sector and rushed reinforcements to the defense of the Don. Not only was German Army Group B delayed by the Soviets that had began to launch counter-attacks in the Axis’ northern flank (which were held by Italian and Hungarian armies), but also by over-extended supply lines and poor road conditions.
On August 10, 1942, German 6th Army had moved to the west bank of the Don, although strong Soviet resistance persisted in the north. On August 22, German forces established bridgeheads across the Don, which was crossed the next day, with panzers and mobile spearheads advancing across the remaining 36 miles of flat plains to Stalingrad. On August 23, German 14th Panzer Division reached the Volga River north of Stalingrad and fought off Soviet counter-attacks, while the Luftwaffe began a bombing blitz of the city that would continue through to the height of the battle, when most of the buildings would be destroyed and the city turned to rubble.
On August 29, 1942, two Soviet armies (the 62nd and 64th) barely escaped being encircled by the German 4th Panzer Army and armored units of German 6th Army, both escaping to Stalingrad and ensuring that the battle for the city would be long, bloody, and difficult.
On September 12, 1942, German forces entered Stalingrad, starting what would be a four-month long battle. From mid-September to early November, the Germans, confident of victory, launched three major attacks to overwhelm all resistance, which gradually pushed back the Soviets east toward the banks of the Volga.
By contrast, the Soviets suffered from low morale, but were compelled to fight, since they had no option to retreat beyond the Volga because of Stalin’s “Not one step back!” order. Stalin also (initially) refused to allow civilians to be evacuated, stating that “soldiers fight better for an alive city than for a dead one”. He would later allow civilian evacuation after being advised by his top generals.
Soviet artillery from across the Volga and cross-river attempts to bring in Red Army reinforcements were suppressed by the Luftwaffe, which controlled the sky over the battlefield. Even then, Soviet troops and supplies continued to reach Stalingrad, enough to keep up resistance. The ruins of the city turned into a great defensive asset, as Soviet troops cleverly used the rubble and battered buildings as concealed strong points, traps, and killing zones. To negate the Germans’ air superiority, Red Army units were ordered to keep the fighting lines close to the Germans, to deter the Luftwaffe from attacking and inadvertently causing friendly fire casualties to its own forces.
The battle for Stalingrad turned into one of history’s fiercest, harshest, and bloodiest struggles for survival, the intense close-quarter combat being fought building-to-building and floor-to-floor, and in cellars and basements, and even in the sewers. Surprise encounters in such close distances sometimes turned into hand-to-hand combat using knives and bayonets.
By mid-November 1942, the Germans controlled 90% of the city, and had pushed back the Soviets to a small pocket with four shallow bridgeheads some 200 yards from the Volga. By then, most of German 6th Army was locked in combat in the city, while its outer flanks had become dangerously vulnerable, as they were protected only by the weak armies of its Axis partners, the Romanians, Italians, and Hungarians. Two weeks earlier, Hitler, believing Stalingrad’s capture was assured, redeployed a large part of the Luftwaffe to the fighting in North Africa.