Many centuries have passed in Narnia since Peter, Susan, Edmund, and Lucy went back to the real world through the wardrobe in The Lion, the Witch, and the Wardrobe. Prince Caspian: The Return to Narnia was originally the sequel to that novel and it is chronologically the fourth volume in The Chronicles of Narnia.
All four children are taken back to Narnia again after a year has passed in the real world; they have been summoned to help the rightful heir to the throne of Narnia claim his kingdom, fight his uncle (the treacherous usurper), and save Narnia from ruin. C.S. Lewis creates many new characters for Prince Caspian, namely the Telmarines, the race of people from the land of Telmar who conquered Narnia in the children’s absence; Prince Caspian, the boy who must be king of Narnia; and Miraz, Caspian’s evil uncle and enemy. Roman and Greek mythology have visible imprints as mythological creatures and beings are in the storyline, e.g. Bacchus, Silenus, and the Maenads. Adventures, nobility, and truth bind the story’s fantastical and realistic elements together, while betrayal and treachery are discussed through the characters’ deeds and behaviors.
Part 4: ‘The Chronicles of Narnia’ by C.S. Lewis, Examiner.com