Galsa Buyeo
Galsa Buyeo or Kalsa 'Puyŏ, also rendered as Galsa-guk, and Hesi Fuyu' in Chinese, was an ancient kingdom founded by an unnamed king of Eastern Buyeo.
History
According to the Samguk sagi, the first king of Galsa, who was then the prince of Eastern Buyeo, feared that his home kingdom would fall into ruins after the assassination of his older brother Daeso in 22 CE.He migrated to the "Galsa River " with 100 followers. The Galsa River, believed to be near the "Amnok Valley ", was the territory of an existing kingdom called "Haedu " where its king frequently visited to hunt.
After noticing the king of Haedu arriving at the valley, it is said that the prince assassinated the king and settled near the Galsa River with his followers, subjugating the previous Haedu kingdom and absorbing its territory. The newly founded kingdom was named "Galsa Buyeo" after the name of the river it was located in, and the kingdom the prince originated from.
It is believed that the kingdom persisted even after its home kingdom of Eastern Buyeo fell to Goguryeo. In fact, Galsa Buyeo was originally on good terms with Goguryeo, to the point where the country was fairly independent. However, in 68 CE, King Dodu of Galsa Buyeo surrendered to Taejo of Goguryeo where he received the respectable bureaucratic position of "U-dae ". His new position is believed to have acted as the head of his kinship, likely the people of the previous Galsa Buyeo.