Key Facts
- Year
- 238 AD
- Wei force size
- 40,000 troops
- Siege duration
- Three months
- Gongsun clan rule
- Three generations of autonomous rule
- Allied support
- Goguryeo assisted Cao Wei
Strategic Narrative Overview
Sima Yi led 40,000 Wei troops into Liaodong and besieged Gongsun Yuan's headquarters. The campaign lasted approximately three months, with the allied support of Goguryeo, one of the Three Kingdoms of Korea, proving significant. The siege culminated in the fall of Gongsun Yuan's stronghold, and Sima Yi ordered the massacre of many who had served the Yan kingdom, effectively destroying its ruling structure.
01 / The Origins
During the Three Kingdoms period, the Gongsun clan had governed Liaodong—present-day eastern Liaoning—independently from the central Chinese government for three generations. Their autonomous rule in the northeast represented a persistent challenge to Cao Wei's authority. Wei general Sima Yi was dispatched to bring the region under central control and eliminate the rival power base of warlord Gongsun Yuan, whose kingdom of Yan operated beyond Wei's direct governance.
03 / The Outcome
Gongsun Yuan's kingdom of Yan was dismantled and Liaodong was absorbed into Cao Wei. The victory eliminated Wei's chief northeastern rival and opened diplomatic and commercial contacts with non-Han peoples of Manchuria, the Korean Peninsula, and the Japanese archipelago. However, subsequent centralisation policies weakened Chinese influence in the region over time, allowing non-Han states to emerge there in later centuries.
Belligerents & Mobilization Analysis
Side A
2 belligerents
Sima Yi.
Side B
1 belligerent
Gongsun Yuan.
Kinetic Engagement Axis
Scroll horizontally to view full axis. Events plotted relatively.