Genghis Khan (Civ6)/Civilopedia

Genghis Khan once demanded two banners: one white horse hide for times of peace, and of black horse hide for all the other times. Upon his death, his soul was alleged to live on in the black Spirit Banner. Some would call this a fitting legacy for the man whose armies terrorized the steppe and whose name has become synonymous with the word 'barbarian.'
At his birth in 1162 CE near the Burkhan Khaldun of Central Asia, he was given the name 'Temujin' by his father Yesugei, a Mongol chieftain, an act of revenge against a captured Tartar foe. His mother, Hoelun, was stolen by Yesugei and would raise Temujin and his siblings in exile after their father was poisoned by the Tartars.
Of course, Temujin would have his revenge.
By 10, the boy would be ostracized by his father's tribe, and by 16 he would kill his half-brother and marry Borte of the Konkirat tribe. All the while, Hoelun would coach her son in statecraft, in influencing allies and controlling enemies.
This would come in handy in his 20s after he was enslaved by former allies, the Taichi'uts. He'd quickly escape and, with his brothers, form a fighting unit, beginning raids of his own, gradually amassing an army of his own. He'd break with Mongol tradition and group fighters according to skill and not blood ties—and Temujin knew how to find skilled fighters.
With a 20,000-strong army, he'd defeat the Tartars and exhibit the brutality he would become known for in avenging his father, ordering the death of every Tartar male above three feet tall. Then he would defeat the Taichi'ut who enslaved him, having them all boiled alive. He would enlist his sons in war as well, sending the eldest, Jochi to conquer Siberia in 1207.
By 1206, his utter ability to destroy his enemies would allow him to unite the tribes of the steppes. That year, he would be given the title 'Genghis (or Chinggis) Khan' or 'universal leader' and issue the Yassa, a collection of divine laws governing everything from property to marriage to civil service designating its execution to his second son, Chagatai.
The Yassa would do away with the common causes of tribal warfare, banning the kidnapping of wives and doing away with inherited titles. He had an empire to control and was loathe to allow internal rivalries.
He would also grant religious tolerance to his followers (as long as they recognized Genghis Khan as the final authority). In this way he would affirm his power, claiming to have been granted it directly from God, and crossing Genghis would be as bad as crossing God. Ask the people of Persian city of Bukhara.
In 1220, the Mongols would begin a 15-day siege to the city after the Shah Ala ad-Din Muhammed killed a delegation of Genghis' ambassadors and traders. Those he did not slaughter Genghis would enslave, telling them he was the flail of God, sent to punish them before their execution.
His warlike ways would get the best of him…well into his 60s. He fell from a horse during the successful campaign against the Xi Xia, and never fully recovering from his injuries. Before he died, he would pass on leadership to his third son, Ogedei, and the Khans would rule an empire extending from East Asia to the Balkans.