In the BooksEdit
As a young Telmarine prince, Caspian was heir to the throne of the kingdom of Narnia. His father, King Caspian the Ninth, was murdered by Miraz, the King's younger brother. When Miraz's own son was born, he attempted to kill Caspian, who fled from the castle and into the woods, where he encountered the Old Narnians – dwarves, fauns, centaurs and Talking Animals, whose ancestors were murdered by the Telmarines who conquered their kingdom and whom the Telmarines believed to be extinct. Caspian took up their cause, but was in need of help to take his throne from Miraz. He blew the magical Horn of Queen Susan, and summoned the four Pevensies back into Narnia. With the assistance of the ancient kings and queens, Caspian and the Narnians defeated Miraz. Caspian was crowned king.
Three years later, Caspian sailed to the End of the World on his ship, the Dawn Treader, accompanied by King Edmund, Queen Lucy, and their cousin Eustace. Along the way, he met the star Ramandu and his daughter, who eventually accompanied Caspian back to Narnia. They married and had a son, Rillian, who disappeared about twenty years later shortly after his mother died of snakebite. Caspian spent years searching for his son, to no avail.
As an old man on his deathbed, Caspian was finally reunited with Rillian after the prince was rescued by Eustace and his friend Jill Pole. Caspian then died and woke in Aslan's Country, Narnian heaven.
In the MoviesEdit
Caspian in the film version of Prince Caspian is dark-haired (as opposed to blond, in the books) and exhibits more angsty tendencies because of his uncle's plot to kill him. The film also inserts a raid on the Telmarine castle that ends in slaughter and failure because Caspian's urge to channel Prince Hamlet (read: kill Miraz) almost gets the better of him. This becomes a point of contention between him and Peter Pevensie. In this vulnerable state, Caspian is persuaded to summon Jadis, who, for some unknown reason, appears in a block of ice. That also doesn't go down well with the Pevensies.
Caspian eventually redeems himself, defeats Miraz, and is crowned King. Due to the nature of films requiring romantic subplots, he is (for some reason) paired with Susan Pevensie (although their kiss only happens at the end, before she returns to England).
In badfic, Caspian is often maligned by being made wangsty and a complete wimp who needs Peter Pevensie to come along and save the day. Either that, or he is made out to be an arrogant brat. He is often paired in het fic with Susan Pevensie thanks to the crowbarred-in romantic subplot of the Movies, or in slashfic with either Peter Pevensie or Edmund Pevensie. Or both.