He was the younger brother of the previous ruler,
King Chimnyu. According to the
Samguk sagi, he ascended to the throne because the heir, later
King Asin, was too young. However, according to the
Japanese
Nihon Shoki he usurped the throne by force. He ordered numerous attacks against
Goguryeo, which was expanding into Baekje territory from the north. In the year 386, he commanded all men living in Cheongmongnyeong (靑木嶺, present-day
Kaesong), above the age of fifteen, to move north and west to defend the borders. He sent the noble Jin Gamo to attack the Goguryeo
Dogon Castle, which was conquered. However, in 392
King Gwanggaeto of Goguryeo counterattacked and seized most of the Baekje territory north of the
Han River. In the tenth month of that year, Goguryeo troops took
Gwanmi Castle and threatened the Baekje palace. According to the
Samguk sagi, Jinsa died while hunting at a satellite palace in Guwon. According to the
Nihon Shoki, Japanese diplomats were sent to Baekje to condemn Jinsa for disrespecting the Japanese emperor, and Jinsa was executed by Baekje as an apology. The Japanese diplomats then put Asin in power and returned to Japan. ==Family==