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.
Economic history of China before 1912
Trade with foreign nations on a large scale began during the reign of Emperor Wu, when he sent the explorer Zhang Yi to contact nations west of China in search of allies to fight the Xiongnu. After the defeat of the Xiongnu, however, Chinese armies established themselves in Central Asia and the Western Regions, starting the famed Silk Road, which became a major avenue of international trade.
In 8 , the Han chancellor Wang Mang usurped the throne of the Han emperors and established his own dynasty, the Xin. Wang Mang wanted to restore the Han to what he believed to be the "idyllic" condition of the early Zhou. He outlawed the trading of land and slaves, and instituted numerous state monopolies. These ultra-modernist policies proved highly unpopular with the population, who overthrew and executed him in 25  and restored the Han dynasty.
Under the Eastern Han dynasty, which followed Wang Mang's overthrow, earlier laissez-faire policies were reinstated, and the government abolished conscription and withdrew from managing the economy. A new period of prosperity and intellectual thought, called the Rule of Ming and Zhang, began. This period saw the birth of the great scientist, Zhang Heng, and the invention of paper. However, by the end of the 2nd century, Han society began to disintegrate. In 184, a peasant preacher started a rebellion called the Yellow Turban Rebellion, which ended the Han dynasty in all but name.
Also known as the Three kingdoms period, the Wei and Jin eras, which followed the collapse of the Han Dynasty, saw large-scale warfare envelop China for the first time in more than 150 years. The death toll and subsequent economic damage were significant. Powerful aristocratic landowners offered shelter to displaced peasants, using their increased authority to reclaim privileges abolished during the Qin and Han. These refugees were no longer taxable by the state. During the Jin, the taxable population was 20 million; during the Han it had been 57 million. Most of North China was unified by Cao Cao, who founded the Wei Dynasty (220–265), and the Jin reunified the remainder of China in 280. The centralised state weakened after losing the tax revenue of those under the protection of large landowners. Nevertheless, the economy recovered slightly under the policies of Cao Cao, who nationalised abandoned land and ordered peasants to encourage peasants to work on them, as well as re-instituting the hated iron monopoly, which would continue under Jin and the Southern Dynasties. Later, the War of the Eight Princes, which, coupled with the a Jin policy of moving the barbarian Wu Hu into China to alleviate labour shortages caused the eventual fall of China.