Sources for Genghis Khan:
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In this encyclopedia article, the conquests of Genghis Khan and the Mongols in western Asia are described. Khan first marched his armies into Khwarizm, the empire boarding his own in the west, when the Mongol envoy to that empire was brutally slain at the command of the Khwarizm emperor, Sultan Mohammed. Enraged, Khan quickly besieged and captured Bukhara and other major cities, which were left without their garrisons to defend them. While Khan dispatched two of his generals to seek and destroy the Sultan and the forces covering his flight, Genghis and his sons defeated and sacked Mohammedís former capitol city. Khwarizm had fallen. The two generals, after eliminating the Sultan and his forces, continued to conquer and destroy enemy militaries to the west wherever they could find them. The Sultan's son, with an army in the south, attacked the Mongol forces in Afghanistan. Khan moved swiftly with his major military force to meet this new attack and the opposing forces were utterly destroyed. While man y more cities were sacked to the west, this concluded the conquest of Genghis Khan in the west. Khan had conquered more territory in less time than any other general in history. His empire was as vast as the world had seen. There was little dissension at the time to the sentiment that Genghis Khan was the greatest conqueror that had ever lived.

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This website depicts the way in which Genghis Khan and his Mongols were able to capture the vast expanse of China. After uniting his own people, Khan drove into China, defeating a small kingdom known as Xi Xia in the north. The Tagnuts, the rulers of northern China, were defeated with a year. After strengthening his ranks, Khan lead his forces into battle against the Qin of central China, overpowering its military, but accepting tribute and a bride from the Qin as a means by which to avoid being conquered. But this peace would not last, and Khan soon returned when hostilities irrupted and destroyed the city of Beijing. Khan, realizing that it would be impossible to wage another military campaign in southern China at the time, left a general in control and returned to Mongolia with the much knowledge, which he had gained from the Chinese and his own military experience. Khan's conquest of the Chinese was the first demonstration of his skill as a general and of his utter brutality. He also learned many things from the Chinese, and acquired technology that would help to bring the ruin of the cities he besieged in central and western Asia.

National Geographic Article
Genghis Khan has gone down in history as one of the greatest conquerors of all time, but this article looks at whether he did more than just conquer. Not only was he a great Mongolian leader, but Khan was also seen as the first man to unify the Mongolian tribes. He was the means by which Mongolia was able to pursue its aspirations of empire. When Khan conquered areas, he was generally tolerant of other religions, though he himself was a worshiper of Tengri, the god of heaven. While he is often considered ruthless, his cruelty was really no worse than the standard of the time; he offered kings the option of tribute and alliance instead of conquest, and many leaders cooperated and added troops to his growing horde. At his greatest strength, Khan brought eighty thousand men to the field, all of them mounted. To have conquered so much with so small a number of men shows that he was also a brilliant tactician. He did, however, drive civilians before his military to act as shields when assaulting enemy cit ies. Opinions differ as to his reasonability, there is clearly an argument supporting the concept of Genghis Khan as more than just a conqueror. His treatment of those who agreed to join with him makes him stand out as a leader who knew that he could use all the help he could get from those who might otherwise have become his enemies.

Sources for Alexander the Great:
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Another article articulates the conquests of Alexander the Great during his own campaigns in western Asia. At the time, in the third century b.c.e., the Persian Empire was the great military power in the region. Alexander vowed to conquer that empire and first lead his forces against the Persian emperor Darius in Asia at Guagamela. Darius' vastly superior military force was annihilated and Darius himself was killed in what is considered one of the greatest military victories by a pathetically outnumbered force of all time. From here, Alexander extends his now enormous empire into Bactria and through the Fertile Crescent, without meeting any serious resistance. When he reaches India, Alexander's army revolts and refuses to continue. Alexander returns by ship to the Persian Gulf, where he rests and prepares for greater conquest. Unfortunately, he is stricken by a fever, never again to lead his armies, and dies soon after. This military campaing leaves Alexander the Great with an empire larger than any of his p redecessors'. Like Genghis Khan, he was able to conquer this massive land area in a remarkably short period of time. His incredible ability to defy odds and numbers made him the greatest conqueror of his era.

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Alexander the Great's creation of Alexandria in Egypt is very well known, and this article spells out some of the wonders to be found there. Alexandria was originally a shady sea port. Alexander chose this city to be his own in 332 b.c.e. and placed there the greatest library in the ancient world. It is speculated that perhaps Aristotle, Alexander's tutor as a child, and his library influenced Alexander in the creation of the library at Alexandria. The library brought scholars in from all over the world, and turned Alexandria into a cultural and educational center of the Mediterranean. The city, with its lighthouse built by the pharos of old, also became a large seaport. The creation of such a cultural city shows that Alexander had a great interest in leaving more than just death in the lands that he conquered. Few other conquerors have ever done so much with a land other than their own nation, and Alexander's investment in the Egyptian city is singular in history.