
I. Establishment and Adjustment of the Administrative System
The formation of the Jiangnan West Route in the Northern Song Dynasty was closely linked to the nationwide reform of the "Route system." When the empire was initially divided into fifteen routes in the 3rd year of the Zhidao era (997 AD), the Jiangnan region had not yet been subdivided. The division of the Jiangnan Route into East and West Routes began in the 4th year of the Tianxi era (1020 AD). The jurisdiction of the Jiangnan West Route included central and southern modern Jiangxi (Hong Prefecture, Ji Prefecture, Qian Prefecture, etc.), while northern Jiangxi areas like Jiang Prefecture (Jiujiang) and Rao Prefecture (Shangrao) still belonged to the Jiangnan East Route. This division was closely related to physical geography: the Gan River basin formed a relatively independent economic unit, whereas Jiujiang and Shangrao had stronger connections to Jiangdong via the Yangtze River waterway.
II. Economic Development and Population Migration
The Jiangnan West Route became a significant granary in the mid to late Northern Song period, with its agricultural development exhibiting three characteristics:
III. Development of Culture and Education
This region experienced a cultural leap in the mid to late Northern Song Dynasty:
IV. Indirect Connections with the Liao Dynasty
Although not directly bordering the Liao, economic interaction occurred through regulated border markets:
V. Finalization of Administrative Divisions
In the 2nd year of the Shaoxing era (1132 AD), the Southern Song adjusted the administrative divisions, transferring Jiang Prefecture and Rao Prefecture from the former Jiangnan East Route to the Jiangnan West Route. This created a pattern largely overlapping with the modern borders of Jiangxi Province. This adjustment was driven both by military defense needs (strengthening control over the middle Yangtze) and reflected the completed economic integration of the Gan River basin.