Yeon Gaesomun
Yeon Ja-yu (Hangul: 연자유, Hanja: 淵子遊, ?-?) was the "Magniji" (Prime Minister) of Goguryeo during its waning days, and was the grandfather of Yeon Gaesomun, who was "Dae Magniji" and dictator of Goguryeo before its fall. Yeon Ja-yu was the father of Yeon Taejo, the father of Yeon Gaesomun, and "Magniji" after Ja-yu. Historical records do not provide his life dates or his actions as "Magniji".