‘I am not the heir of Louis XIV, I am the heir of Charlemagne,’ wrote Napoleon, in one of those moments of epigrammatic self-revelation which are so precious to the students of the most interesting epoch and the most interesting personality of modern history. There are historians who have sought for the origins of the Peninsular War far back in the eternal and inevitable conflict between democracy and privilege: there are others who—accepting the Emperor’s own version of the facts—have represented it as a fortuitous development arising from his plan of forcing the Continental System upon every state in Europe. To us it seems that the moment beyond which we need not search backward was that in which Bonaparte formulated to himself the idea that he was not the successor of the greatest of the Bourbons, but of the founder of the Holy Roman Empire. It is a different thing to claim to be the first of European monarchs, and to claim to be the king of kings. Louis XIV had wide-reaching ambitions for himself and for his family: but it was from his not very deep or accurate knowledge of Charlemagne that Napoleon had derived his idea of a single imperial power bestriding Europe, of a monarch whose writ ran alike at Paris and at Mainz, at Milan and at Hamburg, at Rome and at Barcelona, and whose vassal-princes brought him the tribute of all the lands of the Oder, the Elbe, and the middle Danube...