A study on the subordinate groups of Mohe(靺鞨) Generals Li Duozuo(李多祚) Family immigrated from Koguryo(高句麗) during T’ang dynasty : Focusing on the epitaph of Li Chengsi(李承嗣)

This paper analyzes the epitaph of Li Chengsi(李承嗣), the nephew of Mohe(靺鞨) general Li Duozuo(李多祚), who immigrated from Koguryo, a representative foreign general(蕃將) of the Tang Dynasty in the late 7th and early 8th centuries, and uses this as a clue to identify the reality of the Li Duo-zuo family's subordinate group and reconsider the form of his existence as foreign general. The Mohe group under the Li Duozuo family was a Mohe group that had been under considerably strong Koguryo rule for a long time, and these groups are believed to be Sumo Mohe(粟末靺鞨) groups adjacent to the Huangtou Shiwei(黃頭室韋) located west of Sumo River(速末水). It is highly likely that these groups surrendered together when more than 40 nearby castles surrendered shortly after the fall of Fuyu Castle(扶餘城) of Koguryo, which had jurisdiction over Sumo Mohe, in February 668. After these groups surrendered to the Tang Dynasty at the time of the fall of Koguryo, when the Tang Dynasty established the Protectorate General to Pacify the East(安東都護府) in Koguryo's Pyongyang castle(平壤城) and reorganized the entire land into Jimifuzhou(羈縻府州), Li Yixia(李壹夏), Li Duozuo's older brother, was given to the Doudu of Keshuizhou(可水州都督) and seems to have cooperated with the Tang's Jimi rule. The Mohe group under the Li Duozuo family, which Li Yixia and Li Chengsi had controlled by inheriting the Doudu of Keshuizhou from generation to generation, is judged to have served as an important power base and support base for Li Duozuo's political growth as a foreign general.