Baekje Attacks Pyongyang
King Geunchogo and Crown Prince Geungusu struck Pyongyang with 30,000 men; King Gogugwon of Goguryeo was killed by an arrow defending it.
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With Lelang and Daifang gone, Goguryeo and Baekje met head-on in Hwanghae. In 369 King Gogugwon attacked Chiyang (Baecheon) with 20,000 men and was routed by Crown Prince Geungusu. When Goguryeo came again in 371, Baekje ambushed it on the Paeha (Yeseong) River.
That winter Geunchogo and Geungusu marched on Pyongyang with 30,000 men, and Gogugwon, defending the city, was killed by a stray arrow. The Baekje army withdrew but kept Hwanghae, and Geunchogo moved his capital to Hansan. The next year he sent envoys to Eastern Jin and received investiture.
In Goguryeo, King Sosurim rebuilt the kingdom by adopting Buddhism, founding the Taehak and issuing a law code. Revenge came with Gwanggaeto’s attack on Baekje in 396.