206 - 9 CE (Former Han Dynasty) 25-220 CE (Later Han Dynasty)
The Han Dynasty was the longest empire in China's history. Han Dynasty was unified under a centralized imperial rule by emperor Liu Bang. Technological advancements and inventions of the Han included Paper, collar harness, plow, wheelbarrow, and waterwheel. The social classes under the Han included the emperor. Governors and kings, nobles, scholars and state officials, peasants, artisans, merchants, soldiers, and slaves. Agriculture was vital to the Han Dynasty. Han Wudi set up a Confucianism based imperial university. The taxes collected by the Han dynasty supported the government and the military.