Question

to whom does calibian speak these lines ?how did the person spoken to usurp calibian 's island
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Answer 1

Caliban is the island's only native. As Prospero tells us, he is the product of the witch Sycorax's hook-up with the devil and Caliban was "littered" (a word usually used to describe animals being born, like kittens) on the island after Sycorax was booted out of her home in Algiers (1.2).