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Political History of the Jin Period

Oct 31, 2011 © Ulrich Theobald

The Jin dynasty 晉 (265-420) was founded by Sima Yan 司馬炎 (Emperor Wu 晉武帝, r. 265-289), who hailed from a family of powerful generals and was able to overthrow the house of Cao 曹 that had ruled the empire of Wei 魏 (220-265), one of the Three Kingdoms 三國 (220-280).

The rise of the Sima family

The rise of the Sima family over several generations was due to the political isolation of the Cao family, which was never able to create strong ties to the social elite of northern China. Ancestors of the house of Sima had already served the Later Han dynasty 後漢 (25-220 CE) in high military positions. Sima Yi 司馬懿 (179-251) was one of the most important military leaders of Cao Cao 曹操 (155-220) and his son Cao Pi 曹丕 (Emperor Wen of Wei 魏文帝, r. 220-226) and fought against the sectarian leader Zhang Lu 張魯 (d. 216 CE) of the Five-Pecks-of-Grain Sect (Wudoumi dao 五斗米道), Sun Quan 孫權 (182-252), the eventual founder of the empire of Wu 吳 (222/229-280) in the southeast, and Gongsun Yuan 公孫淵 (d. 238), a warlord controlling the region of Liaodong 遼東 (approx. today's Liaoning) in the northeast. For his military achievements, Sima Yi was given the title of General-in-chief (da jiangjun 大將軍) in 230, and obtained the (honorific) title of Defender-in-chief (taiwei 太尉) in 235.

When Emperor Wen was lying on the deathbed, he chose four regents for his son Cao Rui 曹叡 (Emperor Ming 魏明帝, r. 226-239 CE), one of which was Sima Yi - and the others Cao Zhen 曹真 (d. 231), Cao Xiu 曹休 (d. 228), and Chen Qun 陳群 (d. 236). Unlike the ruling Cao family, the Simas were able to establish by marriage a dense network among the distinguished families. Before Emperor Ming died, he named two regents for his son Cao Fang 曹芳 (r. 239-254), namely Sima Yi, and Cao Shuang 曹爽 (d. 249 CE). The latter immediately bolstered his position, gave the army into the hands of his partisans, the princes Cao Xi 曹羲 (d. 249) and Cao Xun 曹訓 (d. 249), called thinkers and writers like He Yan 何晏 (190–249), as well as Ding Mi 丁謐 (d. 249) to the court, and forced Sima Yi into retirement. After a decade of rest, in 249, Sima Yi decided to backfire. When Cao Shuang accompanied the emperor to a visit at the tomb of his predecessor, Sima Yi, supported by Empress Dowager Guo 郭太后 (d. 264), arrested Cao Shuang and his supporters and had them annihilated.

With the pretext of having defended the imperial house, Sima Yi became the factual regent. He was succeeded in this unofficial function by his sons Sima Shi 司馬師 (208–255) and then Sima Zhao 司馬昭 (211–265). In 260, Sima Zhao was made Counsellor-in-chief (chengxiang 丞相) and ennobled as Duke of Jin 晉. Three years later, he was allowed the nine privileges (jiuxi 九錫), and in 264 raised to the rank of Prince (wang 王) of Jin. He followed a precedent which the Cao family had once pursued when planning to overthrow the Han dynasty. Sima Zhao freely distributed titles of nobility to his followers and partisans. In 266, Emperor Yuan 魏元帝 (r. 260-265) agreed to hand over the throne (see shanrang 禪讓) and the Heavenly mandate (tianming 天命) to Sima Zhao's son, Sima Yan. The foundation of the new dynasty was effected on Feb 8, 266, with a sacrifice to Heaven.

Founding of the Jin dynasty and administrative reforms

Sima Yan took over the complete political and administrative system of the Wei empire, but also its structural weaknesses, particularly the inability of the central government to dominate the local elites and to deprive them of the right of levying taxes and maintaining armies of their own. He freely distributed princedoms (wangguo 王國) to his male relatives, with the hope that this "house power" would support the strength of the dynasty. The Caos had not invested male family members in such a lavish style, and thus had stood relatively lonesome among the ruling elite. In 267, a new, modernized law code (incl. penal law and ritual rules) was promulgated, the Jinlü 晉律, and new procedures for land distribution and taxation (zhantian ketian zhi 占田課田制) were enacted. Land was distributed according to age, gender, and official rank (see nine ranks). State officials had their land cultivated by tenant farmers.

In 280, after a phase of solidification, the conquest of the empire of Wu in the south was begun. It had been initiated with the defection of general Sun Xiu 孫秀 (d. c. 300) to the Jin empire in 270. The conquest itself was directed by Yang Hu 羊祜 (221–278), who drafted a strategy of advancing down the Yangtze River and progressing from the Huai River 淮水 region simultaneously. The Jin advanced on six different fronts, one of which by riverine way. After the conquest of Wu, local military forces were disbanded to strip regional governors (mu 牧) of their military powers. Armies were only left to the capital, and the imperial princes, some of which were appointed area commanders-in-chief (dudu 都督).

The Rebellion of the Eight Princes (291-306)

The fifteen years of power struggles inside the imperial family Sima, by historians called the Rebellion of the Eight Princes (bawang zhi luan 八王之亂) or "disturbances of the Yongjia reign-period" (Yongjia zhi luan 永嘉之亂), indirectly led to the downfall of the Western Jin dynasty 西晉 (265-316).

During the lifetime of Emperor Wu, the court officials disagreed about the question of the successor to the throne. Sima Yan's younger brother Sima You 司馬攸 (248-283), Prince of Qi 齊, who had long been favoured, died untimely. Emperor Wu was therefore eventually succeeded by his son Sima Zhong 司馬衷 (Emperor Hui 晉惠帝, r. 289-306). Emperor Hui was supported in government by Yang Jun 楊駿 (d. 291), a relative of his mother, Empress Dowager Yang 楊太后 (Yang Yan 楊艷, 238-274), who acted as regent for the young ruler. Emperor Hui's wife Empress Jia 賈后 (Jia Nanfeng 賈南風, 257-300) tried to shovel important government posts on to her own family, a pattern of behaviour that had already been in use during the Han period.

Im 291, Empress Jia allowed Sima Wei 司馬瑋 (271-291), the Prince of Chu 楚, to enter the capital with his troops to extirpate the Yang family. The regency of the empire fell into the hands of Sima Liang 司馬亮 (d. 291), the Prince of Runan 汝南, and Wei Guan 衛瓘 (220-291). On order of the Empress, Sima Wei killed the new regent, but he was soon himself eliminated by the Empress. The important governmental posts were thereupon filled with members and supporters of the Jia family, like Jia Mo 賈模 (d. 299), Jia Mi 賈謐 (d. 300), and their supporters like Zhang Hua 張華 (232-300), Pei Wei 裴頠 (267-300), and Wang Rong 王戎 (234-305). After the Empress had in 300 the Heir Apparent Sima Yu 司馬遹 (278-300, Emperor Hui's only son) killed, the other princes rose in rebellion.

Sima Tong 司馬彤 (d. 302), the Prince of Liang 梁, and Sima Lun 司馬倫 (249-301), the Prince of Zhao 趙, entered the capital Luoyang 洛陽 (today in Henan) and killed the Empress and her followers. Sima Lun took over the civil and military government and tried to make himself emperor in 301. Another group of princes under the leadership of Sima Jiong 司馬冏 (d. 302), Prince of Qi 齊, Sima Yin 司馬穎 (279-306), Prince of Chengdu 成都, and Sima Yong 司馬顒 (d. 306), Prince of Hejian 河間, rehabilitated the defenceless Emperor Hui. Sima Jiong took over the crucial government functions. When the new Heir Apparent Sima Shang 司馬尚 (300-302, a son of late Sima Yu) died in 302 without an issue, Sima Jiong installed the minor-age prince Sima Tan 司馬覃 (295-308, a son of Sima Xia 司馬遐, Prince of Qinghe 清河) as heir to the throne. This action provoked a new rebellion, this time led by Sima Yong, Sima Xin 司馬歆 (d. 303), the Duke of Xinye 新野, and Sima Xiao 司馬虓 (270-306), the Prince of Fanyang 范陽. Sima Yi 司馬乂 (277-304), the Prince of Changsha 長沙, killed Sima Jiong and took over the government functions in Luoyang.

The year 303 brought a dramatical increase in belligerent activities. With an enormous army, Sima Ying and Sima Yong beleaguered the capital. Sima Yue 司馬越 (d. 311), the Prince of Donghai 東海, killed Sima Yi and took over the government, residing on his own estates instead of in the capital. In order to secure his grip on Luoyang, he garrisoned an army in the capital. The attempt of Sima Yue, Sima Chi 司馬熾 (284-313), the Prince of Yuzhang 豫章, and Sima Fan 司馬范 (d. 311), the Prince of Xiangyang 襄陽, to overthrow Sima Yue failed. The next attempt to topple him came from the side of Sima Teng 司馬騰 (d. 307), the Duke of Dongying 東瀛, and Wang Jun 王浚 (252-314), regional inspector (cishi 刺史) of the province of Youzhou 幽州 (approx. modern Hebei). They made use of armies staffed with non-Chinese Wuhuan 烏桓 and Xianbei 鮮卑 cavalry. Sima Ying thereupon kidnapped the helpless Emperor Hui and abducted him to the secondary capital Chang'an 長安 (modern Xi'an 西安, Shaanxi). Sima Chi took over the regency for the high-jacked emperor. Only in 306, Sima Yue was able to subdue Sima Ying and finally made an end to the power struggles. Emperor Hui was welcomed back to Luoyang, but passed away in the same year.

During the twelve and more years of power struggle in the northern parts of the Jin empire, the peasant population was afflicted by distress, calamities and hunger. Many peasants had left their fields or the field they had rented, and roamed around the countryside (peasant refugees, liumin 流民) in the search for food and labour.

Since the 290es, numerous rebellions against the disintegrating central government of the Jin dynasty took place. Zhang Chang 張昌 (d. 304) ruled over a vast territory in modern Hubei. Qiu Shen 丘沈 (d. 304) adopted the name Liu Ni 劉尼 and regarded himself as a descendant of the great Han dynasty (which had the family name Liu 劉). He controlled the whole area of the middle and lower Yangtze River. Similar, popular rebellions were staged and led by Wang Ru 王如 (d. 315), Pang Shi 龐實, Hou Tuo 侯脫, Li Xiang 李驤, and Du Tao 杜韜 (d. 315). In Sichuan, the Di 氐 chieftain Li Te 李特 (r. 303) and his descendants founded the Cheng-Han empire 成漢 (304-347), the first of a group of "barbarian" states that eventually controlled northern China for more than one century.

The occupation of north China by Non-Chinese ethnic groups

As early as the last decades of Later Han period and the following power vacuum in the northwest of China, numerous non-Chinese tribes penetrated into areas inhabited by Chinese settlers. They belonged to various ethnicities, like Di, Xianbei (Murong 慕容, Yuwen 宇文, Duan 段, Tuoba 拓拔, Qifu 乞伏, Tuyuhun 吐谷渾), Qiang 羌 or Xiongnu 匈奴. The mosaic-like settlements in the northwest thus created a landscape of ethnic heterogeneity. During the Wei period, the government even promoted the immigration of non-Chinese tribes in order to compensate for the population "deficit" that had accrued during the decades of war and turmoil. In the course of time, most of the non-Chinese tribes became accustomed to Chinese language and culture.

In the first years of the Jin period, many of these tribes were enlisted in the normal household registers (bianhu 編戶) and had to pay taxes and to deliver corvée. Sometimes discriminated, these foreign peoples started to become rebellious against their Chinese suppressors, like Tufa Shuji 禿髮樹機 (a Xianbei chieftain, d. 279) in 270, Liu Meng 劉猛 (a Xiongnu leader, d. 272) in 272, and She San 赦散 (a Xiongnu) in 294. The court of the Jin therefore developed plans to resettle these people to their original homelands.

During the Rebellion of the Eight Princes, many of the belligerents hired non-Chinese troops. The Xiongnu chieftain Liu Yuan 劉淵 (249-310) was bestowed Chinese military titles before he made himself king and then emperor of Han in 308 (later called Former Zhao 前趙, 304-329). One of his followers, the Qiang chieftain Shi Le 石勒 (274-333), was employed as "conquerer of the east". Shi Le became as ruler of the Later Zhao 後趙 (319-350) one of the mightiest and most ruthless "barbarian" rulers and dynastic founders in the fourth century. For 130 years, China would be controlled by the so-called Sixteen Kingdoms of the Five Barbarian Peoples 五胡十六國 (300~430).

The increasing drive of conquest and the rebellions of the non-Chinese population in the north against the Jin dynasty and the local Chinese gentry led to an enormous exodus of Chinese peasants, landowners, and aristocrats to the south, especially into the lower Yangtze area. About one eighth of the northern population fled to the southeast (Holcombe 2019: 97). Many peasants literally ran for their lives. The fleeing landowners took with them their whole households that included slaves, servants, retainers and tenant farmers working on their fields. The imperial household was evacuated relatively late, in 310, when the "barbarians" had already crossed the Yellow River and beleaguered the capital Luoyang. The city fell a year later and was ruined.

Emperor Huai 晉懷帝 (r. 306-312), who had escaped to the alternative capital Chang'an in the west, was captured and killed by the Xiongnu leader Liu Yao 劉曜 (r. 318-329). Sima Rui 司馬睿, the Prince of Langya 琅琊, quickly enthroned Sima Ye 司馬鄴, the Prince of Qin 秦 (known as Emperor Min 晉愍帝, r. 313-316) as the new ruler of the Jin, but the emperor was soon captured by Liu Yao and killed in 317.

Sima Rui decided to adopt the title of Prince of Jin, and a year later took over the throne. He ruled from southeast China as Emperor Yuan 晉元帝 (r. 317-322), while north China and the Sichuan Basin were lost to foreign warlords, many of which founded their own dynasties.

Following to the examples of the Eastern Zhou 東周 (770-221 BCE) and Eastern Han 東漢 (25-220 CE) dynasties that both ruled their domain from the east as a kind of refuge, the unbroken rulership of the Jin dynasty was euphemistically called "Eastern Jin" 東晉 (317-420).

The Eastern Jin government (317-420)

Led by Sima Yue, Sima Fan, and Wang Yan 王衍 (256-311), the imperial household finally crossed the Yellow River and took refuge in the former capital of the Wu empire, Jianye 建業 (modern Nanjing 南京, Jiangsu), that was renamed Jiankang 建康 in order to avoid the similar character 鄴 from the name of late Emperor Min. The number of the surviving members of the imperial family was reduced seriously, and the position of Sima Rui as leader of the imperial house was barely contested. Only one prince acted as a counter-emperor, namely Sima Bao 司馬保 (d. 320), Prince of Nanyang 南陽, in the far west.

The Jin dynasty thereafter ruled from the "exile" in southeast, where Sima Rui, actually not in the lineage of succession, adopted the title of emperor on 23 Apr, 318. Together with the surviving ministers of the central government and the imperial family numerous families of the local elites from northern China had fled to the more secure area of the River Huai and to the lower Yangtze region. Most of them carried their family registers (jiapu 家譜) with them to be able to testify – in case they could return to the north – that they had been owners of large estates. In the first decades after the exodus and escape to the south, the household registers of the northern immigrants were seen as provisional and were therefore written on paper that was not treated with the yellow conservant chemical – hence the difference between the yellow household registers (huangji 黃籍) of the native southerners and the provisional white household registers (baiji 白籍) of the northern immigrants. The exiled persons were grouped according to their districts and commanderies of origin, and were resettled in special refugee districts, commanderies and provinces (qiaoxian 僑縣, qiaojun 僑郡, qiaozhou 僑州). Over time, when it became clear that return to the north would not happen in the near future, refugee households were granted land that was cut off from existing estates (tuduan 土斷). This measure was first enacted in 329, and thereafter carried out in several further rounds. From 389 on, the court discussed the dissolution of the white registers, which was eventually realized in 413.

Most of the high officials at the court of Jianye like Wang Dao 王導 (276-339) or Diao Xie 刁協 (d. 322), were members of the northern elite and magnates. Southerners like Zhou Ji 周玘 (258-313) suddenly saw themselves ruled and dominated by foreign families that had come from the north. Scores of local uprisings against the new domination by the "foreign" Jin elite occurred during the first half of the fourth century, for instance, Zhou Ji's son Zhou Xie 周勰 and his brother Zhou Zha 周札 (d. 324). Wang Dao and Wang Dun were very crucial in convincing the one or other family cluster of southerners to support the Jin regime. In return, quite a few southerners expressed their loyalty to the rightfully ruling Sima family and offered them a new home in the southeast. Some southerners even imitated the northern dialect of the ruling elite. Yet it took more than a hundred years until southerners participated in government affairs in decent numbers. Under the Eastern in, it was just 13 per cent (Holcombe 2019: 100). The émigré elite nonetheless built an esoteric circle and only married among themselves.

A very important aim not only of the ruling class of northerners, but also among the refugees and the intellectuals was to conquer back the north of China. Some of the military campaigns could indeed gain back important territories, like the campaign of Zu Ti 祖逖 (d. 321) in 310 who conquered the River Huai region, the annihilation and conquest of the Cheng-Han empire in 346, or the re-occupation of a great part of modern Shandong by general Liu Yu 劉裕 (363-422). After the victorious Battle of River Fei 淝水 (often falsely written 肥水; perhaps close to Lu'an 六安, Anhui) in 383, the frontier between the Eastern Jin territory and the Former Qin 前秦 (351-394) empire in the north became a stable border for a long time. This balance reassured the southern families who were also interested in political stability, all the more as their political power depended on official appointment and recommendation for participation in examinations.

An internal threat to the Eastern Jin regime were the numerous hill tribes, many of which belonged to the Yue 越 ethnicity or were Man 蠻, Lao 獠 or Li 俚. The Jin were never able to take control of these remote territories, and had to expect the native tribes' resistance against intrusions of both the government and Chinese colonists.

The political history of Eastern Jin is characterized by changing constellations of powerful families and their supporters. These families all belonged to the immigrated northern elite. The first phase is dominated by the family Wang 王 from old Langya 琅琊 (with the main representatives Wang Dao and Wang Dun 王敦, 266-324), the second phase by the Yu family 庾 from Yingchuan 穎川 (led by Yu Liang 庾亮, 289-340), the third phase by the Huan 桓 family from Qiao 譙 (like Huan Wen 桓溫, 312-373), and finally the fourth phase by the Xie 謝 family from Chen 陳 (Xie Shang 謝尚, 308-357, Xie An 謝安, 320-385 and Xie Xuan 謝玄, 343-388).

The rebellions of Wang Dun (322-324), and Su Jun (328-329)

Wang Dao had been a central figure for Sima Rui (Emperor Yuan) to get a foothold in the hostile environment of the southeast. He was therefore regarded as the gray eminence of the Eastern Jin and given the honorific designation Zhongfu 仲父. A popular saying was that "the Wangs and the Simas keep together the empire" (Wang yu Ma, gong tianxia 王與馬,共天下). Wang Dao's cousin Wang Dun was General-in-chief (da jiangjun 大將軍) and regional inspector of Jingzhou 荊州 (approx. Hubei), and thus controlled military affairs of the strategically important middle Yangtze region. He was said to be so powerful that he controlled virtually all civilian and military offices, even if he was not officially regent of the Jin empire.

Emperor Yuan therefore tried to create a balance in the military field in order to check the power of Wang Dun. The decisive persons were Liu Wei 劉隗 (273-333), Diao Xie, Zhou Yi 周顗 (269-322), and Dai Yuan 戴淵 (271-322). Being aware of the threat to his power, Wang Dun set his armies into march against the capital under the pretext of punishing Liu Wei for his insolent conduct. The rebel was able to conquer the capital because there were still no regular city walls around Jiankang and killed three of the ministers, but Liu Wei fled to north China. In the beginning of Wang Dun's campaign, Wang Dao took two dozen of male relatives with him and each morning, when the court audience began, humbly asked for pardon for the rebellion of his cousin. Sima Rui accepted and spared him and on his deathbed even made Wang Dao regent for his young successor Emperor Ming.

After having eliminated his opponents in Jiankang, Wang Dun returned to his seat in Wuchang 武昌 (today's Ezhou 鄂州, Hubei), but when Emperor Ming was inthroned, Wang Dun moved his seat to Gushu 姑孰 (Dangtu 當涂, Anhui) closer to the capital. From there, he was able to exert considerable influence on the court, and was the most powerful man of the time. The emperor secretly prepared for resistance which proved to be a reasonable step because in summer 324, Wang Dun once more marched against the capital. Emperor Ming personally commanded the defence of Jiankang and led a sortie during which the rebel army was successfully destroyed. After Wang Dun's death, the loyalty of his cousin Wang Dao towards the Jin dynasty was rewarded with highest honours.

After only a short rule, Emperor Ming was succeeded by Sima Yan 司馬衍 (Emperor Cheng 晉成帝, r. 325-342), who was assisted by the regents Wang Dao and Yu Liang. The latter desired to eliminate another military figure, Su Jun 蘇峻 (d. 328). In order to forestall his dismissal, Su rose in rebellion and conquered Jiankang. He captured the emperor and his entourage and abducted them to the fortress Shitoucheng 石頭城, a suburb of the imperial capital (today called Qingliangshan 清涼山). In early 329, Emperor Cheng was liberated.

The court under the domination of Huan Wen and Xie An

The first huge explosion between the eminent families occurred after Huan Wen's appointment as military governor (with the prestigious denomination as "General Pacifying the West", anxi jiangjun 安西將軍) of the critical province of Jingzhou. Supporters of the Yu family had claimed the position for themselves, but the court decided in favour of Huan, perhaps because Huan was a brother-in-law of Emperor Cheng. Huan proved to be the right choice when he campaigned against the state of Cheng-Han in Sichuan and conquered this domain in 347. This victory inspired Huan for further advances towards the north. At that moment, the court became critical of his military power and entrusted the northern expedition in 353 to Yin Hao 殷浩 (d. 356), but the latter's advance failed. Emperor Cheng thereupon ordered Huan Wen to take over the command, and Huan was indeed able to advance very near to the ancient western capital Chang'an. In 356, he even occupied the old eastern capital Luoyang, but the city was lost again after barely a decade. Huan's third northern campaign in 369 ended in disaster.

In 371, Huan Wen was powerful enough to regulate the throne succession. He dethroned Sima Yi 司馬奕 (District Duke of Haixi 海西縣公 or "Deposed Emperor" Jin Feidi 晉廢帝, r. 365-371) with the pretext that his sons were illegitimate and made the elderly Sima Yu 司馬昱 (Emperor Jianwen 晉簡文帝, r. 371-372) sovereign of the Jin. The latter died soon and was replaced by Sima Yao 司馬耀 (Emperor Xiaowu 晉孝武帝, r. 372-396), for whom Huan Wen acted as regent. Huan claimed the nine privileges, but the other ministers, led by Xie An, were able to decline, and Huan died shortly later. Even if contemporary sources claim that Huan intended to usurp the throne, he must rather be seen a loyal, but powerful figure among the Jin nobility.

Xie An was a cousin of Empress Dowager Chu 褚太后 (Chu Suanzi 褚蒜子, 324–384) and acted as regent for Emperor Xiaowu. The military threat from the northern states increased with the unification of north China by the Former Qin empire 前秦 (351-394). Xie An therefore gave the military command over the critical defence line of the Yangtze River into the hands of his nephew Xie Xuan, who resided at Jingkou 京口 (today's Zhenjiang 鎮江, Jiangsu). Xie Xuan created a new type of army, the Northern Headquarters Army (beifubing 北府兵) recruited from among the refugee population whose ancestors had come from the north. In 383, the Former Qin launched a large invasion in the eastern parts of the border area, and confronted the Eastern Jin at the banks of River Fei. The battle of River Fei ended in a surprise victory of the Eastern Jin. Historiographers interpreted the battle as decisive for the survival of the Eastern Jin state.

The rebellion of Sun En and the downfall of the house of Sima

The passing away of Xie An enabled the rise of Sima Daozi 司馬道子 (364–403), Prince of Kuaiji 會稽, and his son Sima Yuanxian 司馬元顯 (382–402). The last years of the Eastern Jin dynasty are marked by constant power struggles between the imperial house and the occupants of high government posts. Chancellors, regional inspectors, generals and ministers like Wang Guobao 王國寶 (d. 397), Wang Gong 王恭 (d. 398), and Yin Zhongkan 殷仲堪 (d. 399) fought for influence and power and forged coalitions with princes of the imperial family. In 397, the commander of the Northern Headquarters Army, Wang Gong, rose against the two Simas. A year later, he was joined by a son of Huan Wen, Huan Xuan 桓玄 (369–404), but Wang was tricked and executed a year later, and Huan Xuan became the leader of a powerful military alliance in the middle Yangtze region.

During these years, the decisive rebellion was the religious-led movement of Sun En 孫恩 (d. 402) and Lu Xun 盧循 (d. 411) in 399 and 411. Sun En was head of a Daoist group of the Five-Pecks-of-Grain Sect. Sun En's uncle had been killed by Sima Daozi, who had believed that the Daoist magician negatively influenced Emperor Xiaowu. Sun fled to the island of Zhoushan 舟山 before the coast of present-day Zhejiang, from where he incited a rebellion against the Jin dynasty. Many of the local magnates who felt suppressed by the northern immigrant regime sympathized with the rebellion. One prominent figure, for instance, was Wang Ningzhi 王凝之 (334-399), a son of the calligrapher Wang Xizhi 王羲之 (303–361). After bloods fights, the Jin defeated Sun En's rebellious movement in 402, but the leader's brother-in-law Lu Xun continued resistance. He was forced to withdraw to the far south in Guangzhou and finally in what is today the north of Vietnam. In the course of the Daoist rebellion, Huan Xuan decided to approach the capital under the pretext of rescuing the dynasty, but he met the resistance of the Simas. In 402, Sima Yuanxian fielded the imperial army against Huan Xuan, but Liu Laozhi 劉牢之 (d. 402), the commander of the Northern Headquarters Army, defected to Huan, enabling the latter to occupy Jiankang, where he killed Sima Yuanxian and his father. In 403, Huan Xuan proclaimed himself emperor of Chu 楚.

As the imperial house was wholly impotent against the usurper, the young general Liu Yu was made commander of the Northern Headquarters army. He had proved his military ability in the war against Sun En's rebels, and was indeed able to expel Huan Xuan from Jiankang, yet the usurper took with him Emperor An 晉安帝 (r. 396-418). Huan lost his life during a battle close to Wuchang in 404, and a year later, Liu Yu received the emperor back to the capital. Liu Yu from then on dominated the court, but made himself indispensable by launching several successful campaigns in the northern border zone. He reconquered parts of the Shandong Peninsula in 410, and in the years 416 and 417 liberated Luoyang, and Chang'an, respectively. He was rewarded with the title of Duke of Song 宋 in 418, and bestowed the Nine Privileges. Liu Yu thereupon had Emperor Dezong killed and enthroned his brother Sima Dewen 司馬德文 (Emperor Gong 晉恭帝, r. 419-420), but a year later, enforced the Jin emperor's abdication (shanrang) and founded his own dynasty, the Song or Liu-Song 劉宋 (420-479), the first of the so-called Southern Dynasties 南朝 (420~589). The ex-emperor was killed in 421.

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