Northwestern commander who deposed Mokjong in 1009; captured and killed by the Khitans at Tongju in 1010
When Mokjong's mother, Queen Dowager Cheonchu, and Kim Chi-yang plotted for the throne, he marched into Gaegyeong and destroyed Kim's faction, but also deposed and killed Mokjong. The Khitan used this as a pretext for their second invasion; defeated and captured at Tongju, Gang Jo refused Emperor Shengzong's demand to become his subject and was killed.
Gang Jo marched on Gaegyeong from the northwest, destroyed Kim Chi-yang’s faction, deposed King Mokjong and enthroned Hyeonjong; the Khitans used this as a pretext for their second invasion.
Emperor Shengzong of Liao invaded with 400,000 men and took Gaegyeong; King Hyeonjong fled to Naju, and Yang Gyu harried the retreating enemy and freed captives.
Eighth king of Goryeo, who weathered the second and third Khitan invasions and began the first Tripitaka
Khitan emperor who personally led 400,000 troops into Goryeo in 1010, using Gang Jo’s coup as a pretext
Defender of Heunghwajin who harried the retreating Khitans in 1011, freeing some 30,000 captives before he fell