Grupo de Ejércitos Sur
Hitler had personally intervened in the plans for this operation, and ordered a split in Army Group South. This division of Army Group South had caused alarm in the General Staff, and Hitler was warned repeatedly about the dangers this division entailed. Complaints from the field caused Hitler to dismiss and replace the Commander of Army Group South, Field Marshal Fedor von Bock on July 15. Later studies confirmed this split to be one of the main causes for the eventual demise of the German 6th Army in Stalingrad. Hitler persisted in this division of Army Group South for strategic reasons: acquiring the oilfields in the Caucasus region and cutting Soviet supply transports along the Volga through Stalingrad.