The Arab tribes, which in the last century had been converted, by the genius of Mohammed, from idolatry to the worship of God, and from lawless bandits into disciplined soldiers, were at this period pursuing their career of religious conquest into the heart of Christendom. The Gothic monarchy of Spain, under its last king, Roderick, had fallen beneath the invading force, which now threatened France. The Duchy of Aquitaine, which considered itself independent of France, but which Charles had reduced to comparative submission, opposed the only barrier to Arabian aggression. Eudes (or Eudin), then Duke, was a gallant prince, and did all that in him lay to resist the claim which the new lords of Spain asserted to his province of Septimania (Languedoc). He defeated one invading army before Toulouse in the year 721; but the tide of invasion still flowed in. He then tried intrigue, and bestowed his daughter on Musa, a revolted general of the great Arabian leader, Abd-er-rahman. But all was in vain. In 732 the Moslem once more appeared, in tremendous force, all over the south of France, ravaging as they came, finally besieging Arles and defeating its relieving army. The wives and children of the invaders followed in their train, as though they intended to settle in the country. Abd-er-rahman was advancing yet farther on his victorious way, when Eudes, as a last resource, applied for aid to his enemy, Charles. What were personal enmities now? This common, national danger must be averted at all hazards. So thought Eudes when he sent to Charles. So thought Charles when he quickly summoned an army, and marched toward the plains between Poitiers and Tours, where the Arabs were quartered. The importance of the struggle that ensued cannot well be over-estimated. Christianity and Mohammedanism were at issue for the possession of Europe. The difficulties that lay in the way of the success of Charles were very great. The Arabs were animated with the fanatical zeal of a new faith, and a greedy desire of domination. The Franks, on the other hand, were probably not at all conscious of, or concerned for, the religious interests which were at stake, and aimed at no more than a vigorous rebuff of an unprovoked assault. They had the advantage of familiarity with the country and climate; but were outmatched, beyond comparison, in numbers. The old monkish chronicles tell us that the battle lasted seven days. The Arab army was mainly composed of cavalry and bowmen, and the Franks suffered greatly from the charges of the former and the unerring shots of the latter. But on the seventh day the combatants closed with each other. Heavily fell the iron hands of the sturdy Franks upon the sinewy, but slender frames of their Asiatic opponents. Nevertheless, Charles had no cavalry; and the swift steeds of Arabia, with their daring riders, trampled down his battalions. Suddenly there was a cry in the rear of the Moslem army that the infidels were spoiling the camp.