Pelegosto is a fictional island. The relevant scenes were actually filmed on the lush, tropical island of Dominica.
In Dead Man's Chest, Bootstrap Bill Turner, acting as Davy Jones' agent, delivers the Black Spot to Captain Jack Sparrow, a mark indicating that his blood debt to Jones is due. To avoid the monstrous Kraken that is hunting him, Jack commands the crew of the Black Pearl to land as fast as possible. They alight on Pelegosto, a typical Caribbean island with sandy beaches and lush, mountainous jungles. But it is hardly the paradise it appears, inhabited by a vicious cannibal tribe that captures the Pearl's crew. They believe Jack Sparrow is a god in human form and intend to eat him to "release him from his fleshy prison". Will Turner arrives and helps them escape.
Jack seeks out Tia Dalma, an obeah woman, for help. Dalma lives in a swampy bayou on the Pantano River, located on the island's other side. Mysterious inhabitants live in shacks along the river banks. The island's cannibals avoid this area, most likely fearing Tia Dalma, who, unknown to Jack and the crew, is actually the sea goddess, Calypso, trapped in human form.
According to the film's writers in the Dead Man's Chest DVD commentary, Pelegosto is the same island Jack told Royal Navy Marines, Mullroy and Murtogg about in Pirates of the Caribbean: The Curse of the Black Pearl. He tells them, "and then they made me their chief . . ." before being interrupted by Elizabeth Swann falling off the cliff into the harbor. It is open to conjecture whether or not the cannibals that call the island home recognised Jack when he was again made their chief in Dead Man's Chest.
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