According to the Samguk Sagi, a 12th-century Korean history of the Three Kingdoms, Minjung was the fifth and youngest son of Yuri (Goguryeo's second King), as well as the youngest brother of his predecessor Daemusin. His original name was Hae Saek-ju or Hae Eup-ju, and some scholars believe the king’s surname was Hae.
According to the Samguk Sagi, a 12th-century Korean history of the Three Kingdoms, Minjung was Yuri's fifth and youngest son, as well as Daemusin's younger brother. His original names were Hae Saek-ju or Hae Eup-ju, and some scholars believe his lineage might have been Hae.