Overview
A quartermaster general is the staff officer in charge of supplies for a whole army. He is in charge of quartermaster units and personnel, i.e. those tasked with providing supplies for military forces and units.
Germany
In the Imperial German Army, while a Quartiermeister was a non-commissioned officer in charge of supplies, a Generalquartiermeister did not deal with supplies, but with operational command. He was the most senior officer below an Army's Chief of Staff.
For example, during the First World War, Erich Ludendorff was Generalquartiermeister to the German Second Army in August 1914. With his expert knowledge of the plans for the assault on Liege, which he had helped to draw up, he was sent to supervise that assault and took personal charge when the brigade commander was killed.
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