Osprey's detailed study of the entourage which enabled Napoleon to move hundreds of thousands of troops right across Europe during the Napoleonic Wars (1799-1815). The 'military machine' by which Napoleon and his indispensable chief of staff Marshal Berthier commanded and controlled his huge armies on campaign numbered some 1,500 officers and men, organized in the different bureaux of his military and civilian 'households' and the army general headquarters. This essential tool of the Emperor's power was designed to provide him, even in a front-line camp, with all the information, technical support and comfort that he enjoyed in his palaces.