who was caliban's father?

Caliban is the only authentic native of what is often called 'Prospero's Island'. However, he is not an indigenous islander, his mother Sycorax was from Argier, and his father Setebos seems to have been a Patagonian deity.

Prospero tells us that Caliban’s father was the devil himself, and his mother was Sycorax, a wicked witch. We, however, are not really sure.