Genghis Khan, Mongolian emperor (b. 1162)
Genghis Khan (c. 1158–1162 – August 18, 1227), born Temüjin, was the founder and first Great Khan (Emperor) of the Mongol Empire, which became the largest contiguous empire in history after his death. He came to power by uniting many of the nomadic tribes of Northeast Asia, and, after being proclaimed the universal ruler of the Mongols, or Genghis Khan, he launched the Mongol invasions, which ultimately conquered much of Eurasia, and witnessed raiding as far west as Legnica in western Poland and as far south as Gaza. His major campaigns include those against the Qara Khitai, Khwarezmia and the Western Xia and Jin dynasties, and his generals conducted further raids into medieval Georgia, the Kievan Rus', and Volga Bulgaria.

Genghis Khan and his empire have a fearsome reputation in local histories. Many medieval chroniclers and modern historians describe Genghis Khan's conquests as wholesale destruction on an unprecedented scale, causing great demographic changes and a drastic decline of population as a result of mass exterminations and famine. A conservative estimate amounts to about four million civilians (whereas other figures range from forty to sixty million) who died as a consequence of Genghis Khan's military campaigns. In contrast, Buddhist Uyghurs of the kingdom of Qocho, who willingly left the Qara Khitai empire to become Mongol vassals, viewed him as a liberator. Genghis Khan was also portrayed positively by early Renaissance sources out of respect for the great spread of culture, technology and ideas under the Mongol Empire. By the end of the Great Khan's life, the Mongol Empire occupied a substantial portion of Central Asia and China. Due to his exceptional military successes, Genghis Khan is often considered to be one of the greatest conquerors of all time.Beyond his military accomplishments, Genghis Khan also advanced the Mongol Empire in other ways. He decreed the adoption of the Uyghur script as the Mongol Empire's writing system. He also practised meritocracy and encouraged religious tolerance in the Mongol Empire, unifying the nomadic tribes of Northeast Asia. Present-day Mongolians regard him as the founding father of Mongolia. He is also credited with bringing the Silk Road under one cohesive political environment. This brought relatively easy communication and trade between Northeast Asia, Muslim Southwest Asia, and Christian Europe, expanding the cultural horizons of all three areas.