The place of the thirteenth century in the history of human achievement is a subject upon which scholars have not yet come to a general agreement. There can be no doubt that it was, on the whole, an age of progress in many fields; but there is much in its history that points to stagnation, if not to actual decline. From a superficial study of its annals one might be led to class it with the lesser centuries; most writers are inclined to rank it lower than the fourteenth century, and perhaps not even so high as the twelfth. It was in this period that the crusading movement finally flickered out and the Christian world was compelled to leave the cradle of the holy faith in the hands of the infidel. In the thirteenth century, too, the medieval empire sank into hopeless inefficiency and all but expired. The papacy, which more than any other power was responsible for the ruin of the imperial ambitions, also went into decline. Whether the loss in authority and prestige on the part of the holy see was compensated by a renewed spiritual energy in the church at large may well be doubted: what evidence we have would indicate that the religion of the masses was gross and materialistic, that ethical standards were low, and that the improvement in clerical morals, which the church had hoped would follow the enforcement of celibacy, had failed to appear. Yet the thirteenth century also had its attractive figures and its important movements. The old social order was indeed crumbling, but in its place appeared two new forces which were to inherit the power and opportunities of feudalism and reshape social life: these were the new monarchy, enjoying wide sovereign powers, and the new national consciousness, which was able to think in larger units. In England the century saw the development of a new representative institution, which has become the mother of modern legislative assemblies. The Italian cities were growing rich from the profits of Oriental trade; in the Flemish towns the weaver’s industry was building up new forms of municipal life; the great German Hansa was laying hold on the commerce of the northern seas. In the realms of higher intellect, in science, philosophy, and theology, the age was a notable one, with Roger Bacon, Albertus Magnus, and Thomas Aquinas as the leaders, each in his field. The century also meant much for the progress of geographical knowledge, for it was in this period that Marco Polo penetrated the mysterious lands of the Far East.