Under the Qin, the area was organized as Poyang County (番陽縣) and placed under the administration of Jiujiang.

During the collapse of Qin, he allied first with Xiang Yu and then with Liu Bei, becoming successively the king of Hengshan and then Changsha.

[1] During Eastern Han, the Yangtze River flowed farther north and Poyang constituted a wide and fertile lowland.

Around AD 400, the Yangtze changed its course to the south and flooded the district which has ever since comprised Poyang Lake.

The northern portion of the county is mountainous, while Lake Poyang can be found in the west.