King Cold is the father of Frieza and ruler of an intergalactic empire, just like his son. Much more powerful than Frieza, King Cold rescued his mangled son from the debris of the planet Namek and had him converted into a cyborg.
Once Frieza was revived, Cold travelled with him to Earth, where they planned to wait for Goku's return there and destroy him. However, they were intercepted by Trunks, who sliced and diced Frieza. King Cold decided that Trunks' power must lie in his sword, and thus deceived him into giving it to him- however, he was wrong, and Trunks was able to slay him with a surprise attack when Cold tried to use the sword against him.
King Cold joined with other deceased villains, including his son, Cell and the Ginyu Force (minus Captain Ginyu), in an attempt to take over Hell (HFIL) and escape to conquer the Other World. However, they were stopped by Pikkon and a recently deceased Goku. It is presumed that he and the others are trapped in Hell.