Here, we learn the true story and intentions of Barbossa and his crew. The ship and its crew were once under the command of Jack Sparrow until they mutinied a decade ago, stealing the bearings for Isla de Muerta from him, and then marooning him with a pistol containing only one shot. The island contained a cursed Aztec treasure that the crew of the Black Pearl discovered — but believing the curse to be a myth, they took the Aztec treasure for themselves. Shocked by this action, Will's father, "Bootstrap Bill" Turner, the only pirate who protested against the mutiny, sent one of the cursed gold pieces away to his son in order to ensure a fitting punishment for the crew's betrayal. In retaliation, Barbossa ordered Bootstrap to be tied to a cannonball and thrown overboard. Too late, the crew discovered that the curse was indeed real; in order to break it, they were required to return all the pieces of the treasure to its chest and give a blood sacrifice from everyone who removed them. As part of the curse, the crew's gluttony, greed, and lust for worldly possessions can never be satisfied, and they became undead, forced to never die or rest in their covetousness (moonlight reveals this fact, showing the pirates in its glare to be living, rotting skeletons). After a decade, they have succeeded in fulfilling almost all of the requirements to end the curse — save for obtaining the blood of Bootstrap Bill and the gold piece he stole. With the medallion (in reality, the last piece of the treasure) and Elizabeth "Turner" (who they believe is the child of Bootstrap) in their custody, Barbossa believes he finally has what he needs to lift the curse. here