The principal theme of the novel adheres closely to a mythological template known as the Hero’s Journey. This notion of a world monomyth that all cultures possess was first popularized by professor of comparative religion Joseph Campbell. Eragon follows the mythical archetype in its initial stages. The book begins with Eragon living in the ordinary world as a medieval peasant youth in a rural village. He is soon thrust into the realm of the supernatural when he finds a dragon’s egg that hatches in his presence. His decision to keep the dragon and name her represents another step in the hero’s journey: the call to adventure.

Even though Eragon still has one foot in the ordinary world and goes about his usual daily chores, his attention is now diverted by the need to care for the baby dragon. He is wrenched even further out of the realm of the normal by the arrival of the Ra’zac and the murder of his uncle. Because Eragon’s past has been destroyed, he arrives at a crisis when help appears in the form of Brom. Brom advances Eragon to the next step of the hero’s journey as the mentor who must provide the necessary training to advance the quest.