List of emperors of the Han dynasty
The Han dynasty was founded by the peasant rebel leader (Liu Bang), known posthumously as Emperor Gao ("r". 202 –195 BC) or Gaodi. The longest reigning emperor of the dynasty was Emperor Wu ("r". 141–87 BC), or Wudi, who reigned for 54 years. The dynasty was briefly interrupted by the Xin dynasty of the former regent Wang Mang, but he was overthrown in 23 AD and the Han dynasty was reestablished by Liu Xiu, known posthumously as Emperor Guangwu (r. 25–57 AD), or Guangwu Di. The last Han emperor, Emperor Xian ("r". 189–220 AD), was a puppet monarch of Chancellor Cao Cao (155–220 AD), who dominated the court and was made King of Wei. In 220 AD, Cao's son Pi usurped the throne as Emperor Wen of Wei ("r". 220–226 AD) and ended the Han dynasty.
Government of the Han dynasty
Qin Shi Huang, the first ruler of the Qin dynasty, established China's imperial system of government in 221 BC after unifying the Seven Warring States through conquest, bringing to an end the Warring States period. For a time, the rulers of the warring states claimed nominal allegiance to an overlord king of the Zhou dynasty (c. 1050 – 256 BC), yet the Zhou kings' political power and prestige was less than that of later Chinese emperors. The imperial system fell apart after the fall of Qin in 206 BC. However, following Han's victory over Chu, the King of Han reestablished the imperial system and is known posthumously as Emperor Gaozu (r. 202–195 BC).