In the meantime, the Turks had become a powerful people. They had embraced the Mohammedan religion long before the time of the Crusades, and proved powerful obstacles to the success of those expeditions. About the beginning of the fourteenth century they established an empire of their own in Asia Minor, under Othman or Ottoman, and to this day the Ottoman Empire is a name given to the dominions of their descendants. By degrees they encroached on the borders of the empire of Constantinople, and they were only prevented from subverting it at a much earlier period than they did, by being called upon to defend themselves from the arms of an Eastern conqueror who arose at this time. Tamerlane, otherwise called Timerbek, was a prince of the Usbek Tartars, and a descendant from Ghenghis Khan. After having overrun Persia, and a great part of India and Syria, this great conqueror was invited by some of the minor princes of Asia, who were suffering under the Ottoman tyranny, to come and protect them. Tamerlane was flattered by the request, and having brought a great army into Phrygia, he was there met by Bajazet, the Ottoman emperor, who readily gave battle, but was defeated and made prisoner (1402). Tamerlane made Samarcand the capital of his empire, and there received the homage of all the princes of the East. Illiterate himself, he was solicitous for the cultivation of literature and science in his dominions; and Samarcand became for a while the seat of learning, politeness, and the arts, but was destined to relapse after a short period into its ancient barbarism. The Turks, after the death of Tamerlane, resumed their purpose of destroying the empire of the East. The honor, or disgrace, as it may be thought, of effecting this, fell to the lot of Mohammed II, commonly surnamed the Great. At the early age of twenty-one, Mohammed projected this conquest. His countrymen had already passed into Europe; they had possessed themselves of the city of Adrianople, and indeed had left nothing of all the empire of the East to the Greeks but the city of Constantinople itself. The preparations made for defense were not such as became the descendants of Romans, and the powers of Europe now looked upon the East with the most supine indifference. The Turks assailed the city both on the land side and on that of the sea; and battering down its walls with their cannon, entered sword in hand, and massacred all who opposed them (1453). Mohammed, like many other ambitious conquerors, showed himself unwilling to destroy unnecessarily. The imperial edifices were preserved, and the churches were converted into mosques; the exercise of their religion was freely allowed to the Christians, and this privilege they have never been deprived of. Constantine (for that was the name of the last, as well as the first emperor of the East) was slain in battle. From the time that it was founded by Constantine the Great, the city had subsisted 1123 years. Mohammed liberally