From: http://violet.berkeley.edu/~korea/onjo.html

	The father of King Onjo, founder of Paekche, was 
Chumong.  He fled from North Puyô to escape troubles 
and went to Cholbon Puyô, 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 Puyô, came to Cholbon Puyô and became 
heir to the throne, Piryu and Onjo were afraid of being 
rejected by their half brother and travelled south with ten 
counselors, including Ogan and Maryô.  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 Wiryesông, 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 Koguryô, the ruling family of 
Paekche stems from Puyô, which they adopted as their 
clan name.

Translated by Peter H. Lee