Map Introduction

Administrative Reorganization Following the Western Jin Dynasty's conquest of Eastern Wu, the Yang Province territories previously administered by Eastern Wu were merged with those of the former Cao Wei state to form a unified Yang Province administrative region. Its administrative seat was established in Jianye (present-day Nanjing). This reorganization ended the prior division of Yang Province between Wei and Wu during the Three Kingdoms period, achieving its administrative unification.

Changes in Geographical Scope The jurisdictional scope of Yang Province during the Western Jin period was reduced compared to its territory under Eastern Wu. For instance, commanderies such as Luling and Xindu, which previously belonged to Eastern Wu, were transferred to other administrative districts. Furthermore, newly established areas like Jiangxi and Fujian were placed under the jurisdiction of the newly created Jiang Province. These adjustments reflect the Western Jin court's broader reorganization and integration of the southeastern regions.

Military and Economic Significance The Western Jin regime designated Yang Province as a key strategic base for northern expedition campaigns. Its location in the lower Yangtze River region, with advantageous water transport facilities, established it as a crucial hub for canal transport (caoyun). However, as the political and strategic focus of the central plains regimes remained predominantly in the north, Yang Province's actual influence during this period was limited. It was not until the southward migration of the Eastern Jin court that the region regained its status as a core strategic and economic area.