The Han Dynasty (206 BC–220 AD) followed the Qin Dynasty and preceded the Three Kingdoms in China. The Han Dynasty was ruled by the prominent family known as the Liu clan. The reign of the Han Dynasty, lasting over 401 years, is commonly considered within China to be one of the greatest periods in the history of China. To this day, the ethnic majority of China still refer to themselves as the "Han people".
During the Han Dynasty, China officially became a Confucian state and prospered domestically: agriculture, handicrafts and commerce flourished, and the population reached over 55 million people. Meanwhile, the empire extended its political, cultural influence, and territory over much of Korea, Mongolia, Vietnam, and Central Asia before it finally collapsed under a combination of domestic and external pressures.
The first of the two periods of the dynasty was the Former Han Dynasty or Western Han Dynasty 206 BC–24AD, seated at Chang'an. The Later Han Dynasty or Eastern Han Dynasty 25–220 AD was seated at Luoyang. The western-eastern Han convention is currently used to avoid confusion with the Later Han Dynasty of the Period of the Five Dynasties and the Ten Kingdoms although the former-later nomenclature was used in history texts including Sima Guang's Zizhi Tongjian.
The Han Dynasty was notable also for its military prowess. The empire expanded westward to the Tarim Basin (in modern Xinjiang-Uyghur Autonomous Region), with military expeditions as far west as beyond the Caspian Sea, making possible a relatively safe and secure caravan and mercantile traffic across Central Asia. The paths of caravan traffic came to be known as the "Silk Road" because the route was used to export Chinese silk. Chinese armies also invaded and annexed parts of northern Korea (Wiman Joseon) (as well as establishing colonies and trading posts that eventually integrated with the locals) and northern Vietnam toward the end of the 2nd century BC. The borders near the peripheral territories were often tense with possible conflict with other states. To ensure peace with non-Chinese powers, the Han court developed a mutually beneficial "tributary system". Non-Chinese states were allowed to remain autonomous in exchange for symbolic acceptance of Han overlordship. Tributary ties were confirmed and strengthened through intermarriages at the ruling level and periodic exchanges of gifts and goods.
Within the first three months after Qin Dynasty Emperor Qin Shi Huang's death at Shaqiu, widespread revolts by peasants, prisoners, soldiers and descendants of the nobles of the six Warring States sprang up all over China. Chen Sheng and Wu Guang, two in a group of about 900 soldiers assigned to defend against the Xiongnu, were the leaders of the first rebellion. Continuous insurgence finally toppled the Qin dynasty in 206 BC. The leader of the insurgents was Xiang Yu, an outstanding military commander without political expertise, who divided the country into 19 feudal states to his own satisfaction.
The ensuing war among those states signified the five years of Chu Han Contention with Liu Bang, the first emperor of the Han Dynasty, as the eventual winner with the help of Zhang Liang and Han Xin. Initially, "Han" (the principality as created by Xiang Yu's division) consisted merely of modern Sichuan, Chongqing, and southern Shaanxi and was a minor humble principality, but eventually grew into an empire; the Han Dynasty was named after the principality, which was itself named after Hanzhong ()—modern southern Shaanxi, the region centering the modern city of Hanzhong. The beginning of the Han Dynasty can be dated either from 206 BC when the Qin dynasty crumbled and the Principality of Han was established or 202 BC when Xiang Yu committed suicide.
The new empire retained much of the Qin administrative structure, but retreated somewhat from centralized rule by establishing vassal principalities in some areas for the sake of political convenience. After the establishment of the Han Dynasty, Emperor Gao (Liu Bang) divided the country into several "feudal states" to satisfy some of his wartime allies, though he planned to get rid of them once he had consolidated his power.
After his death, his successors from Emperor Hui to Emperor Jing tried to rule China combining Legalist methods with the Taoist philosophic ideals. During this "pseudo-Taoism era", a stable centralized government over China was established through revival of the agriculture sectors and fragmentations of "feudal states" after the suppression of the Rebellion of the seven states.
Emperor Wu decided that Taoism was no longer suitable for China and officially declared it a Confucian state; however, like the Emperors of China before him, he combined Legalist methods with the Confucian ideal. This official adoption of Confucianism led not only to a civil service nomination system, but also compulsory knowledge of Confucian classics among candidates for the imperial bureaucracy, a requirement that lasted up to the abolition of the civil service examination system in 1905. Confucian scholars gained prominent status as the core of the civil service.
The bureaucratic system of the Han Dynasty can be divided into two systems, the central and the local. As for the central bureaucrats in the capital, it was organized into a head cabinet of officials called the Three Lords and Nine Ministers (三公九卿). This cabinet was led by the Chancellor (丞相), who was included as one of the three lords. Officials were graded by rank and salary, were appointed to posts based on the merit of their skills rather than aristocratic clan affiliation, and were subject to dismissal, demotion, and transfer to different administrative regions. The local official during the former Han Dynasty was different from that of the later Han Dynasty. As for the former Han, there were two administered levels, the county (郡) and the xian (縣). In the former Han Dynasty the xian was a subdivision or sub-prefecture of a county. During the Han period, there were about 1,180 of these xian, or sub-prefectures. The entire Han Empire was heavily dependent upon its county governors (郡太守), as they could decide military policy, economic regulations, and legal matters in the county they presided over. According to historians Ebrey, Walthall, and Palais:
They collected taxes, judged lawsuits, commanded troops to suppress uprisings, undertook public works such as flood control, chose their own subordinates, and recommended local men to the central government for appointments.
The main tax exacted on the population during Han times was a poll tax, fixed at a rate of 120 government-issued coins for adults. For adults there was also the addition of mandatory labor service for one month out of the year. Besides the poll tax, there was also the land tax administered by county and commandeer officials. This was set by the government at a relatively low rate of one-thirtieth of the collected harvest.
With a large amount of revenue in stable times, the Han government was able to fund various public works projects and state infrastructure. In the year 3 AD, a formalized nationwide government school system was established under Emperor Ping of Han, with a central school located in the capital Chang'an and local schools in the prefectures and counties.
As a result of the recorded debate The Discourses on Salt and Iron (Chinese: Yan Tie Lun) about state control over non-renewable resources in China, the state decided to impose government monopolies on salt and iron in the 1st century BC. The government monopoly on salt remained a distinctive feature of the Chinese bureaucracy in subsequent dynasties, although it fell out of use at certain times when merchants were allowed to mine it, refine it, and sell it in free trade.
The intellectual, literary, and artistic endeavors revived and flourished during the Han Dynasty. The Han period produced by birth China's most famous historian, Sima Qian (145–90 BC), whose Records of the Grand Historian provides a detailed chronicle from the time of legendary Xia emperor to that of the Emperor Wu (141–87 BC). Technological advances also marked this period. One of the great Chinese inventions, paper, dates from the Han Dynasty, largely attributed to the court eunuch Cai Lun (50 - 121 AD). By the first (1st) century BC, the Chinese had discovered how to forge the highly durable metal of steel, by melting together wrought iron with cast iron. There were great mathematicians, astronomers, statesmen, and technological inventors such as Zhang Heng (78 - 139 AD), who invented the world's first hydraulic-powered armillary sphere. He was also largely responsible for the early development of the shi poetry style in China. Zhang Heng's work in mechanical gear systems influenced countless numbers of inventors and engineers to follow, such as Ma Jun, Yi Xing, Zhang Sixun, Su Song, etc. Zhang Heng's most famous invention was a seismometer with a swinging pendulum that signified the cardinal direction of earthquakes that struck locations hundreds of kilometres away from the positioned device. There was also continuing development in Chinese philosophy, with figures such as Wang Chong (27 - 97 AD), whose written work represented in part the great intellectual atmosphere of the day. Among his various written achievements, Wang Chong accurately described the water cycle in meteorology. Zhang Heng argued that light emanating from the moon was merely the reflected light that came originally from the sun, and accurately described the reasons for solar eclipse and lunar eclipse as path obstructions of light by the celestial bodies of the earth, sun, and moon.
Military technology in the Han period was advanced by the use of cast iron and steel, which the 1st century engineer Du Shi had made easier by applying the hydraulic power of waterwheels in working the bellows of the blast furnace. The military of the Han Dynasty also engaged in chemical warfare, as written in the Hou Han Shu for the governor of Ling-ling, Yang Xuan, who fought against a peasant revolt near Guiyang in 178 AD:
The bandits were numerous, and Yang's forces very weak, so his men were filled with alarm and despondency. But he organized several dozen horse-drawn vehicles carrying bellows to blow powdered lime strongly forth, he caused incendiary rags to be tied to the tails of a number of horses, and he prepared other vehicles full of bowmen and crossbowmen. The lime chariots went forward first, and as the bellows were plied the smoke was blown forwards according to the wind, then the rags were kindled and the frightened horses rushed forwards throwing the enemy lines into confusion, after which the bowmen and crossbowmen opened fire, the drums and gongs were sounded, and the terrified enemy was utterly destroyed and dispersed.
There were other notable technological advancements during the Han period. This includes the hydraulic-powered trip hammer for agriculture and iron industry, the winnowing machine for agriculture, and the rotary fan and Cardan suspension of Ding Huan (fl. 180 AD).
From 138 BC, Emperor Wu also dispatched Zhang Qian twice as his envoy to the Western Regions, and in the process pioneered the route known as the Silk Road from Chang'an (today's Xi'an, Shaanxi Province), through Xinjiang and Central Asia, and on to the east coast of the Mediterranean Sea.
Following Zhang Qian's embassy and report, commercial relations between China and Central as well as Western Asia flourished, as many Chinese missions were sent throughout the 1st century BC, initiating the development of the Silk Road:
China also sent missions to Parthia, which were followed up by reciprocal missions from Parthian envoys around 100 BC:
By AD 97 the Chinese general Ban Chao had embarked on a military expedition as far west as the landmass encompassed by present-day Ukraine in pursuit of fleeing Xiongnu insurgents, and returned eastward to establish base on the shores of the Caspian Sea with 70,000 men and established direct military contacts with the Parthian Empire, also dispatching an envoy to Rome in the person of Gan Ying.
Several Roman embassies to China are recounted in Chinese history, starting with a Hou Hanshu (History of the Later Han) account of a Roman convoy set out by emperor Antoninus Pius that reached the Chinese capital Luoyang in 166 and was greeted by Emperor Huan. Good exchanges such as Chinese silk, African ivory, and Roman incense increased the contacts between the East and West.
To secure funding for his triumphant campaigns against the Xiongnu, Emperor Wu relinquished land control to merchants and the rich, and in effect legalized the privatization of lands. Land taxes were based on the sizes of fields instead of on income. The harvest could not always pay the taxes completely as incomes from selling harvest were often market-driven and a stable amount could not be guaranteed, especially not after harvest-reducing natural disasters. Merchants and prominent families then lured peasants to sell their lands since land accumulation guaranteed living standards of theirs and their descendants' in the agricultural society of China. Lands were hence accumulating into a new class of landholding families. The Han government in turn imposed more taxes on the remaining independent servants in order to make up the tax losses, therefore encouraging more peasants to come under the landholding elite or the landlords. This could be seen through such examples as the written evidence in the Yan Tie Lun (Discourses on Salt and Iron), written about 80 BC, where the Lord Grand Secretary is quoted in this passage in his support of nationalizing the salt and iron industries:
Formerly the overbearing and powerful great families, obtaining control of the profits of the mountains and lakes, mined iron ore and smelted it with great bellows, and evaporated brine for salt. A single family would assemble a multitude, sometimes as many as a thousand men or more, for the most part wandering unattached plebeians (fang liu ren min) who had traveled far from their own villages, abandoning the tombs (of their ancestors). Thus attaching themselves to the great families, they came together in the midst of mountain fastnesses or desolate marshes, bringing about thereby the fruition of business based on selfish intrigue (for profit) and intended to aggrandise the power of particular firms and factions.
Ideally the peasants pay the landlords certain periodic (usually annual) amount of income, who in turn provide protection against crimes and other hazards. In fact an increasing number of peasant population in the prosperous Han society and limited amount of lands provided the elite to elevate their standards for any new subordinate peasants. The inadequate education and often complete illiteracy of peasants forced them into a living of providing physical services, which were mostly farming in an agricultural society. The peasants, without other professions for their better living, compromised to the lowered standard and sold their harvest to pay their landlords. In fact they often had to delay the payment or borrow money from their landlords in the aftermath of natural disasters that reduced harvests. To make the situation worse, some Han rulers double-taxed the peasants. Eventually the living conditions of the peasants worsened as they solely depended on the harvest of the land they once owned.
The landholding elite and landlords, for their part, provided inaccurate information of subordinate peasants and lands to avoid paying taxes; to this very end corruption and incompetence of the Confucian scholar gentry on economics would play a vital part. Han court officials who attempted to strip lands out of the landlords faced such enormous resistance that their policies would never be put in to place. In fact only a member of the landholding families, for instance Wang Mang, was able to put his reforming ideals into effect despite failures of his "turning the clock back" policies.
The Han government kept records on people's property to assess taxes. Yet government officials and secretaries weren't the only ones documenting property. In the Han period the prototype of contractual language and privately signed contracts appear for those wishing to keep their own private documents on their property for later use in court if necessary. However, creating signed contracts with documented witnesses and scribes was not in common use until the Tang period (618–907), while contractual language did not "permeate Chinese life" until the Yuan Dynasty (1271–1368), according to historians Valerie Hansen and Timothy Brook.
A distant relative of Liu royalty, Liu Xiu, prevailed after a number of agrarian rebellions had overthrown Wang Mang's Xin Dynasty, and he reestablished the Han Dynasty (commonly referred to as the Eastern Han Dynasty, as his capital was at Luoyang, east of the old Han Dynasty capital at Chang'an) in AD 25. He and his son Emperor Ming of Han and grandson Emperor Zhang of Han were generally considered able emperors whose reigns were the prime of the Eastern Han Dynasty. Military speaking, a new golden age also reappeared. In 97, Ban Chao and his troops went as far to reach the Caspian Sea, while this familly also provide notorious generals and historians.
Taiping Taoist ideals of equal rights and equal land distribution quickly spread throughout the peasantry. As a result, the peasant insurgents of the Yellow Turban Rebellion swarmed the North China Plain, the main agricultural sector of the country. Power of the Liu royalty then fell into the hands of local governors and warlords, despite suppression of the main upraising of Zhang Jiao and his brothers. Three overlords eventually succeeded in control of the whole of China proper, ushering in the period of the Three Kingdoms. The figurehead Emperor Xian reigned until 220 when Cao Pi forced his abdication.