The relationship between Prospero and Caliban is one of the more intriguing relationships in Shakespeare's work. Many critics argue that in this master/servant relationship we see a model of the relationship between the colonial powers and the colonised, subjugated slaves of the New World, which was of course of key concern to the audience of Shakespeare's day.
Caliban is described in the play as a "savage and deformed slave," with the word "savage" referring to Caliban's wild and uncivilised nature rather than any cruelty on his part. We need to remember, though, that the descriptions we receive of Caliban emerge from those who have enslaved and debased him. Thus it is that Prospero refers to him as "This mis-shapen knave," and others insultingly refer to him as a "fish" and a "beast." Thus it is that Shakespeare presents us with an age-old tactic of disempowerment: debasing a person by use of language to aid in their subjugation. Again, the history of Caliban that we are given is provided by Prospero, who is hardly unbiased. Although such items of history as Caliban's attempt to rape Miranda are confirmed by Caliban himself, we are left wondering what precisely is the truth concerning the relationship between Caliban and Prospero and more interestingly, what does this relationship suggest about the relationship between colonial powers such as England and their new colonies.