Les 9 Princes d'Ambre (Le cycle des Princes d'Ambre, #1)

First in the "Chronicles of Amber" series of fantasy books. The story begins in the hospital when the protagonist wakes up from a coma with amnesia, his true identity unknown to him. He begins his adventure by visiting his sister and we follow him through the story as he slowly regains his lost memory and real purpose as a member of a royal family of Amber.