The 1942 German Summer Offensive, known as Case Blue (Fall Blau), aimed to capitalize on momentum on the eastern front, using a two-pronged offensive to push into southern Russia and the Caucasus. Army Group South was split into Army Group A, assigned to the Caucasus, and Army Group B, assigned to the Volga area. The Caucasus was a vital oil producing region, supplying 80 per cent of the Soviet Union’s oil at the time, thus making it a key target for Germany, whose oil supply was tight and heavily reliant on Romania. Case Blue opened with fighting in the north of the region in the Battle of Voronezh, designed to keep Russian forces north of Stalingrad and the Caucasus. Despite a quick advance into the Caucasus and the capture of the oil producing city of Maikop during Operation Edelweiss, severe fuel supply issues and the redirection of resources to the battle of Stalingrad halted any meaningful German progress in the region.
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