|Date||Late 4th century BC|
Yan conquers Gojoseon's western territories at Liaodong|
|Commanders and leaders|
In the late 4th century BC, the Yan feudal state invaded the Gojoseon kingdom. The military campaign was led by General Qin Kai. The invasion resulted in Yan's conquest of the Liaodong Peninsula from Gojoseon.
- Yi, Ki-baek (1984). A New History of Korea (Translated ed.). Cambridge: Harvard University Press. ISBN 9780674615762.