During the Middle Ages there was a constant struggle in the West between the two elements of the temporal power--the central, or national, and the local, or that of the great vassals. Gradually the local governments all merged in large aggregates, in each of which a single national government gathered to itself all military, civil, and judicial functions. This movement was already in progress before the end of the thirteenth century. By the end of the fifteenth the struggle was substantially decided, though it did not come completely to an end till the latter part of the seventeenth century. In France, as in most countries, the agent in this organizing and nationalizing movement was the crown. Almost every French monarch did something toward enforcing recognition of the royal authority in all parts of that country which by geographical conditions, as well as by its history, was fitted for political unity. But, either because they did not see their way to undertaking the direct government of so large an area, or because they were themselves under the dominion of feudal ideas, they did not always avail themselves of their frequent opportunities for extinguishing the local governments of the fiefs which fell into their hands. The Valois kings granted many of them as appanages to their younger sons, and so created a new set of great vassals, who revived the struggle for feudal independence. The most dangerous of these, the Duke of Burgundy, openly aided the English invaders. This prince, besides his French fiefs, possessed the yet more important territories now known as Belgium and the Netherlands. Charles VII., the father of Louis XI., having expelled the English, established a permanent force of nine thousand cavalry--the first standing army in modern times.