Onjo of Baekje


Onjo was the founding monarch of Baekje, one of the Three Kingdoms of Korea. According to the Samguk Sagi, he founded the royal family of Baekje.

Background

There are a few theories and legends of Onjo's parentage. One is that he was the third son of King Dongmyeong, the founder of the northern Korean kingdom Goguryeo. He was the younger brother of Yuri, who became Goguryeo's second king, and younger brother of Biryu who built small state in Michuhol.
The second theory is that he is the son of Wutae, his mother's first husband. A third legend says that his older brother Biryu was his mother's son with Wutae but Onjo was born after the second marriage with King Dongmyeong.

Founding and expansion of Baekje

Dongmyeong had three sons: Yuri, Biryu, and Onjo. When Yuri, born from Dongmyeong's previous wife in Dongbuyeo, came to Goguryeo and became the heir to the throne, Biryu and Onjo moved south to found their own kingdoms. According to the Samguk Yusa, Biryu founded his kingdom in Michuhol, but his didn't last long. Biryu's people joined Sipje after Biryu's death and Onjo renamed it to Baekje. After that, the capital city of Baekje was moved southward from Habuk Wiryeseong because the Malgal were located at the North and Nangnang was located to the East. Both capital cities correspond to land within current Seoul. In 13 BC and 8 BC, the Malgal tribes attacked from the north, and both times, Onjo directly led his armies and won victories over the invaders. In 5 BC, Onjo moved the capital city to a more defensible location south of the Han River, renaming it Hanam Wiryeseong, and sent a messenger to the king of the Mahan confederacy telling him of the recent action.
At this time, Onjo already had plans of conquering Mahan and Jinhan. By 7 AD, he was already preparing his armies for war and finally attacked during 8 AD. In 8 AD, he secretly took his armies across the border, laying the deceit that he was going to hunt in the forests. Soon, all of Mahan except for two fortresses were conquered. The citizens of the last two Mahan fortresses surrendered to Onjo and were given mercy. The Mahan King, however, committed suicide and left a letter for Onjo, asking him to take in Mahan's people with kindness and mercy. Onjo respected the Mahan King's last request and took his people in.
Baekje had expanded greatly, and several fortresses were being built every year. Peace lasted for 8 years until 16 AD, when a former Mahan general caused a rebellion. Onjo directly led an army of 5,000 and successfully destroyed the rebellion. Soon after this, the Malgal tribes invaded again during 22 AD, but were once again defeated by Onjo and his army.

Death and succession

Onjo died of natural causes in 28 AD, during the 46th year of his reign. He was succeeded by his eldest son, Daru. Onjo laid the foundations for a powerful dynasty that would last for 678 years and 31 rulers.

Samguk Sagi

"The first ancestor of the Baekje was King Onjo. His father was Chumo, also known as Jumong. From Bukbuyeo he escaped peril and arrived in Jolbon Buyeo. The king of Buyeo was without a male child, and only had three daughters. Upon seeing Jumong, they knew he was not an ordinary man, and made his second daughter wife. Shortly thereafter, the king of Buyeo died. Jumong succeeded him to the throne and had two children. The oldest was called Biryu, and the next was called Onjo. Now Jumong, when he was in Bukbuyeo, had one son, who came and became the crown prince. Biryu and Onjo were afraid that they would not be treated well by the one who had become crown prince, and so with Ogan, Mayeo, and some other ten ministers went south with a large number of commoners following them. Then they reached Mt. Hansan and climbed themselves to the summit to look upon the land where they were. Biryu wanted to settle on the beach, and the ten ministers admonished him, saying "But the land to the south of the river: in the north it is bordered by the Han river, and the East occupied by high mountain peaks; the south faces marshland, and the west is guarded by the sea. This benefits of this divinely strategic land possess a fate not easily acquired. Why should you not make your capital in this place? However Biryu did not listen, and divided the people, and he reverted to Michuhol and settled there. Onjo made his capital south of the river in Wiryeseong, and the ten ministers assisted him, and the country was called Sipje. This happened in the third year of Hongjia, during the reign of Emperor Cheng of the Early Han. Biryu was in Michu, where the earth was wet and the rivers salty, and could not dwell in security. Then he returned to look upon Wirye, where the capital and its villages were stable as a three-legged cauldron, and the people dwelt in security. Then he was ashamed and died. His ministers and people all returned to Wirye. Afterwards in the times that came the people were happy and obedient, and the name was changed to Baekje. Its lineage and that of Kogyureo are both out of Buyeo, therefore they took the surname Buyeo.
One version says, the first ancestor was King Biryu, and that his father was Utae, an illegitimate grandson of the king of Bukbuyeo Hae Buru. His mother was Soseono, a daughter of Yeon Ta-bal, a man of Jolbon. She was married to Utae and gave birth to two sons. The oldest was called Biryu, and the younger called Onjo. Utae died and she was widowed, and settled in Jolbon. After some time Jumong was not well-treated in Buyeo – this was during the second year of Jianzhao in early Han . In spring of the second month, he fled south to Jolbon and established the capital of Goguryeo. He married Soseono and she became his consort, and because she, in the creation of his realm, rendered great assistance, Jumong especially favored them and received Biryu and the other as if they were his own sons. When Jumong was in Buyeo he had a child Yuryu by a woman of the Ye clan, and when he came he was made crown prince and the one who would succeed him. Therefore, Biryu asked his younger brother Onjo, saying “Originally the great king fled the difficulties in Buyeo and escaped here. Our mother's clan poured out the riches of their house to aid in the endeavor , and her toils were many. Now the great king has left this world, and the state has fallen to Yuryu, and if we were to follow along here it would be as depressing as a tumor. Would it not be respectful to our mother's clan if we went to the south and divined the land, and established a separate capital?” Then he and his brother many factions, and crossed the Pae and Dae rivers, and arrived in Michuhol and settled there.
The Pei Shih and Book of Sui both tell that one descendant of Dongmyeong was Gutae who was sincere in his benevolence. When he first established his country in the territory of the former commandery of Daifang, the prefect of the Han territory of Liaodong, Gongsun Du, had his daughter marry . Afterwards became a powerful state among the Eastern Barbarians.
It is unknown which is true ."
Then the king said, “Doing construction at strategic points and protecting the country has been the usual way of things from the past up to now. How dare you change our peaceful relations because of this. You should not have any doubts about this matter! If you presume to lead out a force because of this, then accordingly our tiny country will await you.” Therefore, peaceful relations with Lelang were lost.