Goguryeo–Wei War
[1] Although the king evaded capture and would go on to settle in a new capital, Goguryeo was greatly diminished for a time, and would spend the next half century rebuilding its ruling structure and regaining control over its people, unmentioned by the Chinese historical texts.
[3] In addition, the second campaign of the war included the furthest expedition into Manchuria by a Chinese army up to that time and was therefore instrumental in providing the earliest descriptions of the peoples who lived there.
[6] When the power of the Han dynasty declined to internal turmoil in the 2nd century AD, the warlord Gongsun Du came to control the commanderies of Liaodong (遼東) and Xuantu, directly adjacent to Goguryeo.
Though the candidate supported by Gongsun Kang was eventually defeated, the victor Sansang of Goguryeo was compelled to move his capital southeast to Hwando (present-day Ji'an, Jilin) on the Yalu River, which offered better protection.
However, Han population plummeted in Liaodong as Wei engaged in a large-scale purge of all who served Gongsun Yuan and relocated the coastal populace to Shandong in response to a sea raid from the enemy state Eastern Wu.
The 12th century Korean source Samguk Sagi states that Guanqiu Jian's army invaded in the eighth lunar month of the year, but was twice defeated before winning the crucial battle that sent the king back to the capital.
In contrast, the near-contemporary "Biography of Guanqiu Jian" in volume 28 of Records of Three Kingdoms, containing the Chinese account of this battle, states that King Dongcheon was repeatedly defeated in the tremendous fight at Liangkou and was forced to flee.
Japanese researcher Hiroshi Ikeuchi, writing in 1929 during Japan's period of colonial rule over Korea, asserts that the Korean account was transformed from Guanqiu Jian's biography, reversing the results of the battles before Liangkou.
[22] Nonetheless, both Chinese and Korean sources agree on the fact that King Dongcheon ultimately lost the battle of Liangkou and headed back to Hwando.
Guanqiu Jian first struck the stronghold guarding the main city and then descended upon the capital,[24] where the Wei army wrought much destruction, slaughtering and capturing over thousands of people.
[14][25] Guanqiu Jian specifically spared the tomb and family of Deukrae (得來), a Goguryeo minister who frequently remonstrated against aggression toward Wei and starved himself to death in protest when his advice went unheeded.
[31] The Samguk Sagi relates to an event that purported to have happened in South Okjeo: Yuyu (紐由), another man of the Eastern District, feigned the surrender of King Dongcheon to stop the Wei pursuit.
[34] Turning northwest at the border of Okjeo and the Sushen, they traversed the Mudan River basin (either by way of Ning'an or Dunhua), home of the Yilou people, and crossed the Zhangguangcai Range into the plains on the other side.
Buyeo's regent Wigeo (位居), acting on behalf of the nominal King Maryeo (麻余王), formally received the Wei army outside their capital in present-day Acheng District and replenished their supplies.
[35] Having overextended their reach and lost sight of their target,[2] Wang Qi's army turned southwest from Buyeo to return to Xuantu Commandery, passing by the present-day areas of Nong'an County and Kaiyuan.
[1] Secondly, and more importantly, the intrusions into Okjeo and Ye separated these Goguryeo tributaries from its central ruling structure and brought them back under the influence of the commanderies of Lelang and Daifang.
"[53] In terms of historiography, the expeditions of the second campaign are significant for providing detailed information on the various peoples of the Korean Peninsula and Manchuria, such as Goguryeo, Buyeo, Okjeo, Ye, and Yilou.
The expedition, unprecedented in scale in those regions, brought first-hand knowledge about the topography, climate, population, language, manners, and customs of these areas to Chinese cognizance, and was duly recorded into the Weilüe by the contemporary historian Yu Huan.
[54] Though the original Weilüe is now lost, its contents were preserved in the Records of Three Kingdoms, where the reports from the Goguryeo expedition are included in the "Chapter on Eastern Barbarians" (東夷傳, Dongyi Zhuan) — considered the most important single source of information for the culture and society of early states and peoples on the Korean Peninsula.
