I N THE summer of 1870 the kingdom of Prussia and her German allies totally destroyed the military power of Imperial France. For nearly

There was little precedent in the history of Europe for so dramatic a reversal. To find one we must go back at least to the campaign of Breitenfeld in 1631 when within a few weeks Gustavus Adolphus broke the supremacy of the Catholic powers; and Gustavus had fought for years against the Danes, Poles, and Russians with an accumulating success which already marked him out as one of the great captains of history. In 1870 the Prussian army had to its credit the brilliant campaign of 1866 against Austria, but this was only one in the long series of defeats which the Hapsburgs had suffered at the hands of Prussia and France since the days of Eugene of Savoy. The completeness of the Prussian success in 1870 thus astounded the world. The incompetence of the French high command explained much: but the basic reasons for the catastrophe lay deeper, as the French themselves, in their humiliation, were to discern. The collapse at Sedan, like that of the Prussians at Jena sixty-four years earlier, was the result not simply of faulty command but of a faulty military system; and the military system of a nation is not an independent section of the social system but an aspect of it in its totality. The French had good reason to look on their disasters as a judgment. The social and economic developments of the past fifty years had brought about a military as well as an industrial revolution. The Prussians had kept abreast of it and France had not. Therein lay the basic cause of her defeat.