WORLD HISTORY

Detailed explanation-1: -Despite his accomplishments, Emperor Yang is generally considered by traditional historians to be one of the worst tyrants in Chinese history and the reason for the Sui dynasty’s relatively short rule.

Detailed explanation-2: -The great enemy of the Chinese was the Mongols who lived to the north. They even built a wall thousands of miles long to try and keep the Mongols from invading. The Mongols did conquer China for a time, however, and established their own dynasty called the Yuan Dynasty.

Detailed explanation-3: -The Zhou Dynasty made significant cultural contributions to agriculture, education, military organization, Chinese literature, music, philosophical schools of thought, and social stratification as well as political and religious innovations.