Jeongan
The Jeongan Kingdom (정안국, 938-986) was a successor state of Balhae founded by Yeol Manhwa. The official Chinese historical record, the History of Song states that Jeongan derives from Mahan.
When Khitan Liao Dynasty forces deposed Balhae in 926, a few officials of the fallen kingdom, led by the Dae clan, established Later Balhae. However, in 935, General Yeol Manhwa took control of the government after the death of the Dae clan king, and changed the state name to Jeongan. Jeongan is recorded to have enlisted the assistance of neighboring tribes with the hopes of overthrowing the Khitan, but apparently failed to do so. The Yeol clan was replaced by the Oh clan in 976, and was ruled by Oh Hyeon-myeong until before it was finally destroyed by the Khitan in 986 CE.
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