Kim Won-sul was a member of the Silla's Jinggol class, and rose to the rank of Low-level general by the time of Goguryeo's fall to the Silla-Tang Alliance.
General Won-sul was near Baeksu Castle in August of the year 672, fighting Tang dynasty troops.
However, they chased the retreating Chinese troops and fell into a trap that killed seven generals and countless soldiers.
Won-sul answered, “A man never lives a humiliating life" and then whipped his horse to make a dash.
Kim Yu-sin, a former hwarang, asked King Munmu to execute Won-sul for retreating from battlefield instead of dying with honour.
In June 673, people witnessed several dozen crying soldiers in armor with weapons in their hands walking out of Yu-sin's home.
Kim Won-sul spent the rest of his days, starving in the mountains, and died in an unknown year at an early age.