Answer:
Your answer is Genghis Khan united the tribes of Mongolia.
Explanation:
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.
Native peoples of America had no immunity to the diseases that European explorers and colonists brought with them. Diseases such as smallpox, influenza, measles, and even chicken pox proved deadly to American Indians. Europeans were used to these diseases, but Indian people had no resistance to them.