In 1210, Genghis Khan receives a delegation from the Jurched people in modern Manchuria (northern China). They are a major economic force, controlling trade from the cities of China into the Asian interior. The delegation announces the ascension of their new ruler, the Golden Khan, and demands submission. Genghis insults them instead, provoking war. He calls a khuriltai and the tribal leaders give their consent to a southern campaign. The campaigns against the Tangut had given him experience in crossing deserts and attacking walled cities, but no experience in siege, in which the Mongols have to improvise. They cut off food and supplies to the Jurched cities, and attempt to divert their water source, the Yellow River. Weatherford describes this campaign as the first match in a “conflagration” that led eventually to world conquest.

Weatherford next describes the travel methods of the Mongol army. Each man carried what he needed, and the army rarely ate hot food; the absence of cooking fires made them harder to detect. Since the Mongols had no infantry and no supply train, they were more maneuverable than their enemies. Also, they were stronger than the agricultural peoples they encountered due to their protein-heavy diet.