Yan's Invasion of Gojoseon

Overview

This was an incident in which Qin Kai (秦開), a general of the Warring States-period state of Yan (燕), attacked and seized the western territory of Gojoseon. It is recorded in the Weilüe (魏略) quoted as a commentary in the Han (韓) section of the Dongyi Zhuan (東夷傳) in the Records of the Three Kingdoms (三國志), and it is the first record in the documents of Gojoseon directly clashing with Chinese power.

The exact year is not recorded. Academia places it during the reign of King Zhao of Yan (昭王, r. 311–279 BCE), that is, around the early 3rd century BCE. The -300 in this document is an approximate point in time. The map marker is placed on the presumed location of Manbeonhan (滿番汗), which became the new boundary (roughly southwest of Hai Cheng in Liaodong to the Gai Zhou area).

Background

According to the Weilüe, when the Zhou royal house declined and Yan declared itself a king and tried to expand its territory eastward, the Marquis of Joseon (朝鮮侯), said to be a descendant of Jizi (箕子), also declared himself king, raised troops, and attempted to attack Yan. However, the grand master (大夫) Ye (禮) dissuaded him and he stopped; Ye was then sent to Yan to persuade it, and Yan also halted its attack. This record shows that around the 4th century BCE Gojoseon had grown into a political power capable of confronting Yan. The Shiji (史記) biography of Su Qin (蘇秦列傳) and the Zhanguo Ce (戰國策) also mention that during the reign of Duke Wen of Yan (燕文侯, r. 361–333 BCE), Joseon lay to the east of Yan.

Course of Events

The Weilüe records that afterward the descendants of the Marquis of Joseon grew increasingly arrogant and violent, so Yan sent the general Qin Kai to attack their western territory. Yan seized more than 2,000 li of land and reached Manbeonhan, setting it as the boundary, and it is said that "Joseon thereupon weakened (朝鮮遂弱)." The Shiji Biography of the Xiongnu (匈奴列傳) also records that Qin Kai defeated the Donghu (東胡) and forced them to retreat more than 1,000 li, showing that Yan's eastward advance targeted both the Donghu and Gojoseon. Yan then built a Great Wall from Zaoyang (造陽) to Xiangping (襄平) and established five commanderies: Shanggu (上谷), Yuyang (漁陽), Youbeiping (右北平), Yaoxi (遼西), and Liaodong (遼東).

Results and Impact

• Loss of territory: Gojoseon lost its western domain in the Liao River basin. The "Gojoseon" entry of the Encyclopedia of Korean Culture (한국민족문화대백과사전) holds that Gojoseon afterward faced Yan across the area of the Cheongcheon River.
• Theory of shift of center: There is a view (the theory of shift of the center) that following this defeat, the center of Gojoseon moved from Liaodong to Pyongyang in the Daedong River basin.