Eastern Buyeo
Dongbuyeo (86 BCE - 410 CE) was an ancient Korean kingdom that developed from Bukbuyeo, until conquered by the early Goguryeo, which then grew into one of the Three Kingdoms of Korea. According to the Samguk Sagi, it was established when Buyeo's king Hae Buru moved the capital eastward by the sea.
Founding
According to the Samguk Sagi and other accounts, the kingdom of Dongbuyeo branched out to the east of Bukbuyeo, near the land of Okjeo.
Hae Buru found a golden frog-like child under a large rock. Hae Buru named the child Geumwa, meaning golden frog, and later made him crown prince.
Early Eastern Buyeo
Geumwa became king after Hae Buru's death. Not long after, King Geumwa reversed his father's submission to Bukbuyeo and declared himself "Supreme king" and gave the title posthumously to his father, Hae Buru. At Ubalsu, south of Taebaek Mountain, Geumwa met Yuhwa, the disowned daughter of Habaek, and brought her back to his palace. She was impregnated by sunlight and laid an egg, from which hatched Jumong.
Geumwa's two sons resented Jumong, and although Geumwa tried to protect him, Jumong ran away to Jolbon Buyeo, where he later established Goguryeo.
Geumwa's eldest son Daeso became the next King. King Daeso attacked Goguryeo during the reign of its second ruler, King Yuri. Goguryeo's third ruler King Daemusin attacked Dongbuyeo and killed King Daeso. After internal strife, Dongbuyeo fell, and its territory was absorbed into Goguryeo.
Later Eastern Buyeo
According to other records, Jumong was from Bukbuyeo, not Dongbuyeo. According to the Gwanggaeto stele, Dongbuyeo was a tributary of Goguryeo. Dongbuyeo was briefly revived by a small state established around 285 by refugees of Buyeo. This state was conquered by King Gwanggaeto of Goguryeo.
Although the chronology is inconsistent with the Samguk Sagi, one legend says Wutae, the father of the Baekje's founder and 1st ruler, Onjo, was a son of Hae Buru.