For centuries the Mongols were divided into tribes. In 1206, Genghis Khan unified the tribes and took power over them. He built a strong army and demanded complete loyalty. He set out on a conquest to expand his empire. The Mongols were brutal. They burned any town or city that resisted them and killed all of the people. They conquered much of Asia. When Genghis Kahn died in 1227, the Mongols controlled much or Northern China, and Central Asia. He left his Empire to his sons and grandsons. The empire was divided into four areas called ''Kahnates". Divided among the heirs of Genghis Khan.
Kublai Khan was one of the Khanates became one of the great rulers of Mongolia. In 1235, Kublai Khan went on the mission to take southern China ruled by the Song. The Song put up much resistance to the Mongols for many years. In 1279, the Mongols defeated the last Song ruler. Kublai Khan proclaimed himself emperor. The Mongols now controlled all of China. He did not force the Chinese to accept the Mongolian way of life. He set the capital near Beijing. He was accepting of the Chinese ways. Although, marriage was illegal between the Mongols and Chinese. He created different laws and taxes and didn't allow the Chinese to own weapons or be in the military. Chinese officials could only serve at a local level. He expanded the Grand Canal and made trade easier between Northern and Southern China. Near the end of Kahn's rule, he tried to invade Japan and suffered terrible loses. He was weakened and the Chinese rebelled. After he died, there wasn't any good ruler to take his place and the Chinese won their rebellion.