The German wars of unification in 1864, 1866 and 1870-71 were of world historical significance. But their impact was not just limited to the realm of politics. In terms of military history these wars represented a watershed in the process of change affecting the scope and nature of cabinet warfare between the European powers. The change from ‘cabinet war’ to industrialised ‘people’s war’ (Volkskrieg), 1 which had been on the horizon since the Crimean War, was all but completed in the Franco-Prussian War. Until the First World War and beyond, the military and political consequences of this change were among the key problems of all strategic calculations and, indeed, of all deliberations on the point and the objectives of war and the options open to it in the industrial age. The strategic planning and the policies of the German General Staff before 1914 focused on the question of what military responses were most appropriate to deal with the problems raised by the transition to the age of people’s war. This essay attempts to clarify this issue, which is fundamental to any understanding of the military policies of Imperial Germany in general, and of strategic planning in particular.