Kings of the Han dynasty
The kings from other dynasties (, "yìxìng wáng") were mostly remnants of the rebellion against the Qin dynasty. Following the Dazexiang Uprising, many noblemen rose in rebellion. Heirs, pretenders, and warlords called themselves "kings" and claimed sovereignty as continuations of the six states previously suppressed by Qin. Among these, Chu was the most powerful. However, its rightful ruler Huai II was assassinated on the orders of the warlord Xiang Yu and the 18 Kingdoms Xiang had formed rose in rebellion against him. Liu Bang, king of Han, ultimately defeated Chu and established the new Han dynasty. The kings who had sided with him were then permitted to maintain their titles and lands. A few other kingdoms were also formed by Liu Bang for generals and favorites.
History of the Han dynasty
The long life of Empress Wang Zhengjun (71 BCE–13 CE), wife of Emperor Yuan and mother to Emperor Cheng, ensured that her male relatives would be appointed one after another to the role of regent, officially known as Commander-in-Chief. Emperor Cheng, who was more interested in cockfighting and chasing after beautiful women than administering the empire, left much of the affairs of state to his relatives of the Wang clan. On November 28, 8 BCE Wang Mang (45 BCE–23 CE), a nephew of Empress Dowager Wang, became the new General-in-Chief. However, when Emperor Ai of Han (r. 7–1 BCE, Liu Xin) took the throne, his grandmother Consort Fu (Emperor Yuan's concubine) became the leading figure in the palace and forced Wang Mang to resign on August 27, 7 BCE, followed by his forced departure from the capital to his marquessate in 5 BCE.
Due to pressure from Wang's supporters, Emperor Ai invited Wang Mang back to the capital in 2 BCE. A year later Emperor Ai died of illness without a son. Wang Mang was reinstated as regent over Emperor Ping of Han (r. 1 BCE – 6 CE, Liu Jizi), a first cousin of the former emperor. Although Wang had married his daughter to Emperor Ping, the latter was still a child when he died in 6 CE. In July of that year, Grand Empress Dowager Wang confirmed Wang Mang as acting emperor ("jiahuangdi" 假皇帝) and the child Liu Ying as his heir to succeed him, despite the fact that a Liu family marquess had revolted against Wang a month earlier, followed by others who were outraged that he was assuming greater power than the imperial Liu family. These rebellions were quelled and Wang Mang promised to hand over power to Liu Ying when he reached his majority. Despite promises to relinquish power, Wang initiated a propaganda campaign to show that Heaven was sending signals that it was time for Han's rule to end. On January 10, 9 CE he announced that Han had run its course and accepted the requests that he proclaim himself emperor of the Xin dynasty (9–23 CE).