The Prussian army was controlled by the General Staff, under Field Marshal Helmuth von Moltke. The Prussian army was unique in Europe for having the only such organisation in existence, whose purpose in peacetime was to prepare the overall war strategy, and in wartime to direct operational movement and organise logistics and communications. The officers of the General Staff were hand-picked from the Prussian Kriegsakademie (War Academy). Moltke embraced new technology, particularly the railroad and telegraph, to coordinate and accelerate mobilisation of large forces.
What entity controlled the Prussian army?
the General Staff