Born to the noble family of Yesugei and Ho'elun. At an early age(nine years old) he married Borte(from another tribe). At the time when he was away with his wife's tribe his father, Yesugei was poisened and killed by Tatars. Yesugei displaced the Mongols as the strongest tribe in eastern Mongolia. Yesugei's followers deserted his widow and children, who were then forced to live in condition of great hardship. According to The Secret Histroy of the Mongols he endured many hardships, including the kidnapping of his wfie Borte. Temüjin survived by hunting and fishing.
After rising to power in 1185, Temuchin experienced numerous setbacks and, eventually, victories. A key to his success was an alliance with his father's blood brother, Toghril Ong-Khan, King of the Keraits (another tribe). With Toghril's support, Temuchin regained Borte and slowly became the paramount power in the steppe. Eventually, relations between Temuchin and Toghril soured and led to a war that left Temuchin victorious. By 1206 Temuchin dominated Mongolia and received the title Genghis Khan.
Although Genghis Khan now ruled Mongolia and had united the various tribes into one tribe he was not content to remain there.
In 1207, the Mongols began operations against Xi-Xia, which comprised much of northwestern China and parts of Tibet. This campaign lasted until 1210 with the Xi-Xia ruler submitting to Genghis Khan. During this period, the Uighurs also submitted peacefully to the Mongols and became valued administrators throughout the empire.
Peace did not last long. In 1211, after a great quriltai or meeting, Genghis Khan led his armies against the Chin Dynasty that ruled northern China. War continued against the Chin until 1234, well after Genghis Khan's death. Perhaps he would have succeeded against them, but he was pulled away from the campaign because of an incident in central Asia(Uzbekistan, Turkmenistan, Iran, Afghanistan, and Tajikistan).
From 1219 to 1222, the Mongols waged a war in central Asia and destroyed the Khwarazmian Empire. Striking from several directions, Genghis Khan-accompanied by his four sons: Jochi, Ogodei, Chaghatai, and Tolui-carried out a campaign that remains strategically remarkable. Though a few Khwarazmian princes escaped, the defeat was complete; but Genghis Khan still had a matter of revenge to settle.
Even today the legacy of Genghis Khan remains impressive. His wars were often a matter of retaliation as well as bids for territory or riches. As an organizational and strategic genius, Genghis Khan created one of the most highly-disciplined and effective armies in history.
Genghis Khan's greatest accomplishments, however, cannot be counted in terms of territory or victories, but in the presence of a Mongol nation and culture. Mongols today venerate him as the founding father of Mongolia.
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