The outbreak of the Seven Years War saw the formation of new alliances and led to the conduct of military operations in several theaters simultaneously. The campaign of 1757 saw large-scale maneuvers, with their necessary operational corollaries of supply and logistics, as France put an army of 100,000 men into the field. The conduct of the campaign also testifies to the difficulty of exercising command in the face of a court and a government for which short-term results took precedence over means. Notwithstanding such difficulties, the campaign of the French armies in Westphalia saw its climax play out around the village of Hastenbeck on 26 July 1757, where the forces of Maréchal d'Estrées gained a victory that came close to knocking Hanover out of the war.The story of the campaign can be told from the human perspective thanks to the large body of memoirs and letters from officers, both general and subordinate, of cavalry and infantry regiments. Having left their garrisons four months earlier, they had come to battle at the gates of Hanover after having traveled more than 600 kilometers through the Low Countries and into Germany.