Go Deokmu

Go Deokmu (고덕무, 高德武) (r. 699-?) was a prince of Goguryeo and the founder of Lesser Goguryeo. He was the third son of King Bojang.

Go Deokmu was appointed to the position of Governor of the Protectorate General to Pacify the East in 699, after his nephew Go Bowon refused the position. Go Deokmu took advantage of this situation and also declared independence from the Tang, establishing Lesser Goguryeo. The Tang had no choice but to accept an envoy from Lesser Goguryeo and recognize it as an independent state. Go Deokmu took control of the Liaodong peninsula and the Korean Peninsula north of the Taedong River. The location of Go Deokmu's capital or when he died is unknown.

Go Deokmu's Lesser Goguryeo lasted for 120 years, being absorbed into Balhae in 819, during the reign of King Seon.

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