The territory of the Western Jin empire 西晉 (265-316) was almost as large as that of the Han empire 漢 (206 BCE-220 CE), and the administration structure with regions or provinces (zhou 州) and subordinated commanderies (jun 郡) and princedoms (wangguo 王國, in the map in violet) was also inherited from the Han local administration. "Princedom" territories given to imperial princes were to be found in the eastern regions of the empire. In 302 some of the prince rose up against the central government, and the empire was shaken in its foundations by the rebellion of the eight princes (underlined yellow). From the beginning of the fourth century CE numerous rebellions spread disturbances within the Jin empire. The leaders of these rebellions (large yellow dots) were partially Chinese peasants or soldiers like Qi Wannian 齊萬年, Wang Ru 王如, Zhang Chang 張昌, Hao San 郝散, Wang Mi 王彌 and Du Tao 杜弢, and partially non-Chinese chieftains like Tufa Shujineng 禿髮樹機能 in modern Gansu and Li Te 李特 in Sichuan. At the same time, non-Chinese tribes that had immigrated into Chinese territories several decades before, fought against the local governors and founded their own states that should become known as the Sixteen Barbarian States 五胡十六國 (300~430). The internal disturbances did not allow wide prospects for the Jin government to engage in international trade with the Korean (Samhan/Sanhan 三韓 "Three Han": Mahan 馬韓, Chinhan/Chenhan 辰韓, Pyŏnhan/Bianhan 弁韓; Koguryŏ/Gaogouli 高句麗, Fuyu/Puyŏ 夫余, Okchŏ/Woju 沃沮 and Yemaek/Huimo 濊貊) or Japanese kingdoms (Wa/Wo 倭).
Driven away by the rebellion of non-Chinese tribes in northern China the Jin court in 317 CE fled the ancient capital Luoyang 洛陽 (modern Luoyang, Henan) and founded a new capital in the southeast in Jiankang 建康 (modern Nanjing 南京, Jiangsu) in the lower Yangtze region. North China was given up and was for more almost three centuries controlled by non-Chinese states. The border between south and north was a permanently changing frontier. The years in the map give the approximate date of the most important border changes. Until 420 the government of the Eastern Jin empire 東晉 (317-420) was able to regain a substantial part of territory south of the Yellow River.
After the escape to the south, a part of the local administration structure of the north was simply moved to the south, and areas and commanderies from the north were installed as a temporary southern mirror for their original place. Therefore some regional designations can be found in the area of modern Jiangsu province that were formerly located in Shandong, Henan or even Hebei, like the provinces of Qingzhou 青州, Yanzhou 兖州 and Youzhou 幽州. Likewise, virtual commanderies were installed in the hope to return the to the north once later, like Qi 齊 or Nan-Qiao 南譙.
During the last decades of the Eastern Jin period several rebellions, uprisings and civil wars (yellow dots) substantially weakened the central government. The most important activities were the rebellion of Sun En 孫恩 in 399-402 and that of Xu Daofu 徐道覆 from 402 to 411.