The migrated provinces, commanderies and counties were consequence of a special administrative regionalization called qiao zhi during the Six dynasties era of China. The Shahumyan Province is a modern analogue of their alternative local government, in their infancy. With adoption of tu duan and merger, these nominal subdivisions transitioned to the actual administrative divisions.
Background
Since the invasion of the five barbarians, a large number of northern refugees migrated south. These migrants who called "qiao ren " were the base of the migrated provinces, commanderies, and counties. Bearing northern place names, they were set up by Eastern Jin. Such a move was not unprecedented, the central government migrated the whole commandery or county to a new place as early as Han dynasty. However, they emerged on a massive scale since Eastern Jin.
History
During the Emperor Yuan, Emperor Ming and Emperor Cheng period, the migrated provinces, commanderies and counties were concentrated in the area south of the Huai River and the Lower Yangtze Plain. The earlier typical classic examples was migrated Langya Commandery within migrated Fei County in Jiankang, but they were certainly not the earliest. At least migrated Huaide County was established in there, around 320 before that. According to the Book of Song:
claiming to the occupied northern territory and evoking people's desire to resume
deadening the homesickness of qiao ren
manifesting the higher status of the qiao ren who came from the aristocratic clans
attracting the Han Chinese in the North cross the border to pledge to the South authorities
fostering economic growth
The belts where qiao ren lived subdivided into 3 administrative levels, similar to the ordinary administrative divisions:
migrated provinces or qiao zhou
migrated commanderies or qiao jun
migrated counties or qiao xian
After Emperor Wu of Liu Song recaptured some lost northern territory, some of them there were prefixed with "north" or "bei" to distinguish them from their migrated counterparts in the south. After Liu founded the Liu Song, the prefix bei was dropped while migrated place names that had derived from their prototypes in the north took on the prefix "south" or "nan". Still, there were a few exceptions to prefixed with "east" or "dong" and "west" or "xi". For instance, Dong Jingzhao and Xi Jingzhao. As time goes by, the migrated provinces, commanderies and counties plunged the administrative divisions into chaos. For instance, Yinping County was located in the southeastern part of Gansu Province nowadays initially. While it had four migrated counterparts.
Development
Baiji and huangji
Considering most property of qiao ren had been lost or exhausted as they arrived, they were privileged to be free from diao, a special poll tax was paid via the silken or cotton cloth etc in the ancient China, and service. Their registers which bound in white papers were called baiji in Chinese. The ordinary ones which bound in yellow papers were called huangji in comparison. Over a given period, baiji was a preferential identification states the bearer's hometown. The imperial court had a specific intent, which scarcely be succeeded,to sort out hukou conveniently in the future after regaining the lost territory.
Once the situation settled down and the population swelled, the considerable amount of northerners flooding into the south magnified the economic and social problems. Reforms were clearly in order. Hence, tu duan was an increasingly important issue for the Eastern Jin and the subsequent Southern dynasties.
Tu duan policy
The tu duan is the abbreviation for yi tu duan. The terms were firstly mentioned in the Book of Jin:
It was a solution to put an end to the chaos the migrated provinces, commanderies and counties brought, and ensure the hukou system operated smoothly. Ten times in total tu duan implemented in the Eastern Jin and the Southern dynasties.
Had misgivings about the potential conflict of interest, the government was obliged to meet some qiao ren, especially the constituent parts of the , halfway every time the policy was implemented.
