Gojoseon-Yan War

Gojoseon–Yan War
Date Late 4th century BC Location Liaodong Peninsula Result Yan victory Territorial changes Yan conquers Gojoseon's western territories
Belligerents
Yan	Gojoseon

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.

During the last half of the 4th century BC, the state of Qi, which lies to the south of Yan, began to apply pressure against Yan. In order to prevent invasion, by way of making themselves stronger, Yan decided to invade Gojoseon.

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