The father of King Onjo, founder of Paekche, was Chumong. He fled from North Puy˘ to escape troubles and went to Cholbon Puy˘, whose king had no son but had three daughters. Knowing that Chumong was extraordinary, the king presented his second daughter to him in marriage. Shortly thereafter, the king died and was succeeded by Chumong. Chumong had two sons, Piryu and Onjo. When Yuri, a son of Chumong, born in North Puy˘, came to Cholbon Puy˘ and became heir to the throne, Piryu and Onjo were afraid of being rejected by their half brother and travelled south (http://violet.berkeley.edu/~korea/legends.html#journey) with ten counselors, including Ogan and Mary˘. Many followed them. Upon reaching Hansan, they climbed Pua Peak (Mount Samgak) to find a place to settle. When Piryu wished to settle by the sea, the counselors advised him: "The land south of the Han borders the Han River to the north, takes to a high mountain to the east, views a fertile marsh to the south, and is separated by a great sea to the west. Its natural fastness is unparalleled, a place fit for your capital." But Piryu did not listen. He divided the people and went to Mich'uhol to settle. Onjo set up his capital at Hanam Wiryes˘ng, made ten counselors his assistants, and named his country Sipche. This was in the third year of Hung-chia of Emperor Cheng of the Former Han [18 BC]. Because the land of Mich'uhol was wet and its water salty, Piryu could not live in comfort; when he returned and saw Wirye firmly established and its people happy, he died of shame and remorse. His followers pledged allegiance to Wirye and joyfully came to submit, hence the country was named Paekche. Like Kogury˘, the ruling family of Paekche stems from Puy˘, which they adopted as their clan name.
Translated by Peter H. Lee (http://violet.berkeley.edu/~korea/legends.html#phl)