Within fifty years from the death of Mohammed, the Saracens had raised an empire, not only temporal, but also spiritual, more extensive and more powerful than what remained of the empire of Constantinople; and within a hundred, they had subdued not only Persia, Syria, Asia Minor, and Arabia, but also Egypt, North Africa, and Spain. It seemed, indeed, in the course of the eight century, as if Asia and Europe both should yield to their victorious arms, and become one great Mohammedan dominion. But the mighty fabric, of mushroom growth, crumbled into dust with equal speed. After the first extension of their conquests, they ceased to acknowledge any one head of their empire, and the successful generals of the provinces contented themselves by paying a religious respect to the caliphs of Bagdad, as the successors of the prophet, while they retained the power of conquerors for themselves. In the year 732 they sustained a great defeat in France from Charles Martel, who became the father of an illustrious race of kings. No fewer than 375,000 Saracens are said to have been left dead on the field of this battle, and it is certain that they never after cherished the hope of subduing Europe. About the middle of the ninth century (848), they projected the conquest of Italy, and even laid siege to Rome itself. But they were entirely repulsed by Pope Leo IV; their ships were dispersed by a storm, and their army cut to pieces. Spain was the only European country in which they were able to obtain a permanent footing, and in it alone have they left traces of their existence. FROM THE DESTRUCTION OF ROME TO THE AGE OF CHARLEMAGNE――ORIGIN OF THE FEUDAL SYSTEM.