Parnival Plunder was the younger brother of Kevin Plunder. When their father, Lord Robert Plunder discovered the Savage Land, word leaked out and he sent Kevin to live there and Parnival to live as a sailor to keep them safe. Believing Kevin had been killed, Parnival established himself as the lord of Castle Plunder as a front for his criminal activities as the Plunderer. Upon learning that his step-brother had survived in the Savage Land as Ka-Zar, the two clashed on several occasions.
During the Civil War, the Plunderer sought out refuge with Captain America (Steven Rogers). However, the Punisher seemingly executed Goldbug and the Plunderer before Captain America could stop him. Later, hired by Roxxon, Plunderer revealed that he had sent an impersonator to Cap, and that was the man killed by the Punisher, though he encouraged the belief that he was dead.