Han Dynasty

The Han dynasty (, ; ) was an imperial dynasty of China (202 BC – 9 AD, 25–220 AD), established by Liu Bang (Emperor Gao) and ruled by the House of Liu. The dynasty was preceded by the short-lived Qin dynasty (221–207 BC) and a warring interregnum known as the ChuHan contention (206–202 BC), and it was succeeded by the Three Kingdoms period (220–280 AD). The dynasty was briefly interrupted by the Xin dynasty (9–23 AD) established by usurping regent Wang Mang, and is thus separated into two periods—the Western Han (202 BC – 9 AD) and the Eastern Han (25–220 AD). Spanning over four centuries, the Han dynasty is considered a golden age in Chinese history, and it has influenced the identity of the Chinese civilization ever since. Modern China's majority ethnic group refers to themselves as the "Han people", the Sinitic language is known as "Han language", and the written Chinese is referred to as "Han characters".

The emperor was at the pinnacle of Han society. He presided over the Han government but shared power with both the nobility and appointed ministers who came largely from the scholarly gentry class. The Han Empire was divided into areas directly controlled by the central government called commanderies, as well as a number of semi-autonomous kingdoms. These kingdoms gradually lost all vestiges of their independence, particularly following the Rebellion of the Seven States. From the reign of Emperor Wu ( BC) onward, the Chinese court officially sponsored Confucianism in education and court politics, synthesized with the cosmology of later scholars such as Dong Zhongshu. This policy endured until the fall of the Qing dynasty in 1912 AD.

The Han dynasty saw an age of economic prosperity and witnessed a significant growth of the money economy first established during the Zhou dynasty ( BC). The coinage issued by the central government mint in 119 BC remained the standard coinage of China until the Tang dynasty (618–907 AD). The period saw a number of limited institutional innovations. To finance its military campaigns and the settlement of newly conquered frontier territories, the Han government nationalized the private salt and iron industries in 117 BC, though these government monopolies were later repealed during the Eastern Han dynasty. Science and technology during the Han period saw significant advances, including the process of papermaking, the nautical steering ship rudder, the use of negative numbers in mathematics, the raised-relief map, the hydraulic-powered armillary sphere for astronomy, and a seismometer employing an inverted pendulum that could be used to discern the cardinal direction of distant earthquakes.

The Han dynasty is known for the many conflicts it had with the Xiongnu, a nomadic steppe confederation to the dynasty's north. The Xiongnu initially had the upper hand in these conflicts. They defeated the Han in 200 BC and forced the Han to submit as a ''de facto'' inferior and vassal partner for several decades, while continuing their military raids on the dynasty's borders. This changed in 133 BC, during the reign of Emperor Wu, when Han forces began a series of intensive military campaigns and operations against the Xiongnu. The Han ultimately defeated the Xiongnu in these campaigns, and the Xiongnu were forced to accept vassal status as Han tributaries. Additionally, the campaigns brought the Hexi Corridor and the Tarim Basin of Central Asia under Han control, split the Xiongnu into two separate confederations, and helped establish the vast trade network known as the Silk Road, which reached as far as the Mediterranean world. The territories north of Han's borders were later overrun by the nomadic Xianbei confederation. Emperor Wu also launched successful military expeditions in the south, annexing Nanyue in 111 BC and Dian in 109 BC. He expanded Han territory into the northern Korean Peninsula as well, where Han forces conquered Gojoseon and established the Xuantu and Lelang Commanderies in 108 BC.

After 92 AD, the palace eunuchs increasingly involved themselves in the dynasty's court politics, engaging in violent power struggles between the various consort clans of the empresses and empresses dowager, causing the Han's ultimate downfall. Imperial authority was also seriously challenged by large Daoist religious societies which instigated the Yellow Turban Rebellion and the Five Pecks of Rice Rebellion. Following the death of Emperor Ling ( AD), the palace eunuchs suffered wholesale massacre by military officers, allowing members of the aristocracy and military governors to become warlords and divide the empire. When Cao Pi, king of Wei, usurped the throne from Emperor Xian, the Han dynasty ceased to exist.

Etymology

According to the ''Records of the Grand Historian'', after the collapse of the Qin dynasty the hegemon Xiang Yu appointed Liu Bang as prince of the small fief of Hanzhong, named after its location on the Han River (in modern southwest Shaanxi). Following Liu Bang's victory in the Chu–Han Contention, the resulting Han dynasty was named after the Hanzhong fief.

History

Western Han

China's first imperial dynasty was the Qin dynasty (221–207 BC). The Qin united the Chinese Warring States by conquest, but their regime became unstable after the death of the first emperor Qin Shi Huang. Within four years, the dynasty's authority had collapsed in the face of rebellion. Two former rebel leaders, Xiang Yu (d. 202 BC) of Chu and Liu Bang (d. 195 BC) of Han, engaged in a war to decide who would become hegemon of China, which had fissured into 18 kingdoms, each claiming allegiance to either Xiang Yu or Liu Bang. Although Xiang Yu proved to be an effective commander, Liu Bang defeated him at the Battle of Gaixia (202 BC), in modern-day Anhui. Liu Bang assumed the title "emperor" (''huangdi'') at the urging of his followers and is known posthumously as Emperor Gaozu ( BC). Chang'an (known today as Xi'an) was chosen as the new capital of the reunified empire under Han.

At the beginning of the Western Han (), also known as the Former Han () dynasty, thirteen centrally-controlled commanderies—including the capital region—existed in the western third of the empire, while the eastern two-thirds were divided into ten semi-autonomous kingdoms. To placate his prominent commanders from the war with Chu, Emperor Gaozu enfeoffed some of them as kings.

By 196 BC, the Han court had replaced all but one of these kings (the exception being in Changsha) with royal Liu family members, since the loyalty of non-relatives to the throne was questioned. After several insurrections by Han kings—the largest being the Rebellion of the Seven States in 154 BC—the imperial court enacted a series of reforms beginning in 145 BC limiting the size and power of these kingdoms and dividing their former territories into new centrally-controlled commanderies. Kings were no longer able to appoint their own staff; this duty was assumed by the imperial court. Kings became nominal heads of their fiefs and collected a portion of tax revenues as their personal incomes. The kingdoms were never entirely abolished and existed throughout the remainder of Western and Eastern Han.

To the north of China proper, the nomadic Xiongnu chieftain Modu Chanyu ( BC) conquered various tribes inhabiting the eastern portion of the Eurasian Steppe. By the end of his reign, he controlled Manchuria, Mongolia, and the Tarim Basin, subjugating over twenty states east of Samarkand. Emperor Gaozu was troubled about the abundant Han-manufactured iron weapons traded to the Xiongnu along the northern borders, and he established a trade embargo against the group.

In retaliation, the Xiongnu invaded what is now Shanxi province, where they defeated the Han forces at Baideng in 200 BC. After negotiations, the ''heqin'' agreement in 198 BC nominally held the leaders of the Xiongnu and the Han as equal partners in a royal marriage alliance, but the Han were forced to send large amounts of tribute items such as silk clothes, food, and wine to the Xiongnu.

Despite the tribute and negotiation between Laoshang Chanyu ( BC) and Emperor Wen ( BC) to reopen border markets, many of the Chanyu's Xiongnu subordinates chose not to obey the treaty and periodically raided Han territories south of the Great Wall for additional goods. In a court conference assembled by Emperor Wu ( BC) in 135 BC, the majority consensus of the ministers was to retain the ''heqin'' agreement. Emperor Wu accepted this, despite continuing Xiongnu raids.

However, a court conference the following year convinced the majority that a limited engagement at Mayi involving the assassination of the Chanyu would throw the Xiongnu realm into chaos and benefit the Han. When this plot failed in 133 BC, Emperor Wu launched a series of massive military invasions into Xiongnu territory. The assault culminated in 119 BC at the Battle of Mobei, when Han commanders Huo Qubing (d. 117 BC) and Wei Qing (d. 106 BC) forced the Xiongnu court to flee north of the Gobi Desert, and Han forces reached as far north as Lake Baikal.

After Wu's reign, Han forces continued to fight the Xiongnu. The Xiongnu leader Huhanye Chanyu ( BC) finally submitted to the Han as a tributary vassal in 51 BC. Huhanye's rival claimant to the throne, Zhizhi Chanyu ( BC), was killed by Han forces under Chen Tang and Gan Yanshou () at the Battle of Zhizhi, in modern Taraz, Kazakhstan.

In 121 BC, Han forces expelled the Xiongnu from a vast territory spanning the Hexi Corridor to Lop Nur. They repelled a joint Xiongnu- Qiang invasion of this northwestern territory in 111 BC. In that same year, the Han court established four new frontier commanderies in this region to consolidate their control: Jiuquan, Zhangyi, Dunhuang, and Wuwei. The majority of people on the frontier were soldiers. On occasion, the court forcibly moved peasant farmers to new frontier settlements, along with government-owned slaves and convicts who performed hard labor. The court also encouraged commoners, such as farmers, merchants, landowners, and hired laborers, to voluntarily migrate to the frontier.

Even before the Han's expansion into Central Asia, diplomat Zhang Qian's travels from 139 to 125 BC had established Chinese contacts with many surrounding civilizations. Zhang encountered Dayuan