As Temüjin grew up into a young man, he developed other qualities that set him apart. He had a lot of charisma and was able to persuade people to have faith in him and help him. Once, for example, when he was pursuing a thief who had stolen his family's horses, he encountered a stranger who was so impressed by him that he not only gave Temüjin a fresh horse to ride but joined him in recovering the stolen animals. In another instance, when his young bride was kidnapped by a tribe called the Merkit, Temüjin in desperation went to Toghril, the leader of another tribe, the Kereit, and gave him a sable skin that was one of his own wedding gifts. That leader then not only helped Temüjin rescue his wife, but pledged to be his military ally [source: Bawden].
As Temüjin built such alliances, he developed into a formidable warrior with a reputation for treating those who dared to oppose him with extreme brutality. He avenged his father's murder by the Tatars by slaughtering all of the males who were taller than the height of a cart's axle, and then enslaved the women and children. As a result, the enemy tribe basically ceased to exist [sources: Edwards, Bawden].
Amid the shifting intrigue and struggle for power within the Mongol tribes, Temüjin turned on former allies with the same ferocity. When he was in his early forties, his old ally Toghril and his childhood friend Jamuqa, both of whom had aided him in his rise, decided to oppose him. Temüjin beat Toghril's Kereit army in a fierce three-day battle, and then absorbed his soldiers into his own force. In 1205, he defeated the last powerful tribe that opposed him, and captured and executed Jamuqa — though he did grant his friend's last wish to get it over with quickly [sources: Edwards, Bawden].
There was no one left to challenge Temüjin. In 1206, the Mongol tribes held a kurilai, or great assembly. They proclaimed Temüjin as the ruler of all, and gave him a new name, Genghis Khan.
But he was just getting started.