Jolly Roger was a mythological pirate captain of the 18th-century Caribbean Sea who, according to an old legend, was supernaturally transformed into an undead skeleton as the result of a curse which came from his betrayal of a voodoo priest who had failed him in his quest to cheat Captain Jack Sparrow out of his seat on the Brethren Court. According to an old mariners' tale, Jolly Roger was a bad-tempered pirate captain who performed unsavory deeds for the Brethren Court until he attempted to usurp Captain Edward Teague's seat on the Brethren Court after Teague passed down the title of Pirate Lord of the Caribbean Sea to his son, Jack Sparrow. After he failed to steal Sparrow's title in a high-stakes game of poker, Roger killed the card dealer, the voodoo priest Amo Dorsi, who, in his dying breaths, cursed Roger to walk the earth as the undead. Roger lost his humanity, but he acquired the ability to raise the dead with his supernatural breath, creating an army of undead skeletons with the objective of conquering the Caribbean for himself, proclaiming himself a Pirate Lord, and having his revenge against Jack Sparrow and the pirates.