Heeresgruppe B
Case Blue ("Fall Blau"), launched 28 June 1942, saw Army Group South divided into two Army Groups, Army Group A and Army Group B, the former participating in the Battle of the Caucasus. Throughout the operation the German situation, especially that of Army Group B centered on Stalingrad, began to deteriorate. As Army Group B began collapsing in the North, Army Group A quickly found itself at risk of being flanked. It was forced to abandon its task of securing the oilfields of the Caspian, and began withdrawing down the Terek River toward the Taman Peninsula.