After the destrucion of Koguryo, the remaining people in Manchuria started to restore themselves. Tae Cho-yong, a former general, led the remaining people of Koguryo and the Mohe tribe to found Parhae. It was located in the area of Dongmiaoshan in Dunhuxian. Parhae reconquered almost all of the old Koguryo territory and dominated Manchuria. In the early 9th century, under the rule of King Son, Parhae occupied a large territory reaching out from the Heilung River (Amur) to the north, Yonghun in Hamgyonganam-due south, the Maritime Province to the east, and Kaiyuan to the west. During the Parhae Dynasty, sea trade developed greatly.

At the end of the 9th century, Shilla was split into three territories known as the Later Three Kingdoms. Paekche became Later Paekche, and Koguryo became Later Koguryo. In 918 AD, King Kung'ye, the founder of Later Koguryo, was driven out by his subjects to put Wang Kong into power. In 918 Wang Kong became King and changed Later Koguryo to Koryo. In 925, King Kyongsun, the last sovereign of Shilla, ceded his sovereignty to Koryo. A year later, Koryo attacked Later Paekche. When Paekche was destroyed in 936, Koryo unified the Later Three Kingdoms.