The Hobbit’s main theme is Bilbo’s development into a hero, which more broadly represents the development of a common person into a hero. At the beginning of the story, Bilbo is timid, comfortable, and complacent in his secure little hole at Bag End. When Gandalf talks him into embarking on the quest with Thorin’s dwarves, Bilbo becomes so frightened that he faints. But as the novel progresses, Bilbo prevails in the face of danger and adversity, justifying Gandalf’s early claim that there is more to the little hobbit than meets the eye.

Bilbo possesses hidden reserves of inner strength that even Bilbo himself cannot perceive when he firsts sets out on the quest. Confronting the trolls, escaping with Gollum’s ring, slaying the spider, rescuing the dwarves in Mirkwood, and speaking face-to-face with the great dragon Smaug all provide Bilbo with opportunities to test his resolve. As he builds confidence and resourcefulness, Bilbo emerges as a true hero.

Because Tolkien acknowledged that the idea of hobbits was rooted in his experiences with rural Englishmen of his own time, Bilbo’s development might allegorically represent the heroism of England in World War I or the inner, latent heroism common to everyone. But given Tolkien’s stated distaste for allegory—his main motivation for writing was storytelling, not the exploration of a literary theme—it is questionable whether Bilbo’s story should be taken to refer to anyone except Bilbo himself.

The differences among Tolkien’s imaginary races are a major focus of the novel, particularly in its second half. Elves, dwarves, trolls, and goblins differ from one another physically, psychologically, and morally. These inherent racial differences drastically limit the possibility of individual choice but make moral distinctions easy to maintain. All goblins are evil, for example, and all elves are good. The notion of races having different moral qualities is reflected in the novel’s idea of nature. The good races are portrayed as being in harmony with nature, while the evil races are depicted as being at odds with it—hence the eagles’ decision to help the elves against the goblins. Some critics have suggested that the different races in The Hobbit were meant to represent different European nationalities, but Tolkien’s distaste for allegory makes this seem highly unlikely.

Family lineage is another important factor that shapes identity in The Hobbit. Throughout Middle-Earth, one’s prospects, character, and social position are linked closely to family heritage. Bilbo’s conflicting feelings of fear and courage, for instance, are portrayed as a struggle between his Baggins side and his Took side, referring respectively to his father’s and his mother’s families. Thorin is prompted to seek the treasure under the mountain because it is his birthright, passed down from his grandfather, Thror. Bard’s heroism is in part attributed to his having descended from the lords of Dale. Whereas race is primarily a determinant of one’s moral standing, family has more to do with one’s specific personality: Bilbo is good because he is a hobbit, but he is adventurous because he is a Took.

Tolkien was a scholar of ancient languages at Oxford. A major source of inspiration for The Hobbit’s plot was the body of ancient epic literature that Tolkien studied, particularly Scandinavian and Anglo-Saxon epics like Beowulf. Elements of the story originate from literature, including the form of the heroic quest, the dragon’s treasure hoard, the importance of named swords, the elves’ mysterious magic, and the grim focus on birthright and family lineage.

The Hobbit revisits many of these ancient conventions with a playful, comic tone that is thoroughly modern. Bilbo himself, with his common sense, love of peace, and warmhearted self-doubt, is in many ways a rural Englishman of the 1930s transplanted into a medieval adventure. Tolkien’s exploration of this contrast between the world in which he lived and the worlds he studied is the source of a large part of the book’s comedy. This contrast also has some thematic importance—Thorin’s last words to Bilbo indicate that despite the grandeur of epic heroism, the simple modern values of the hobbits perhaps have a more important place in the world.

Since The Hobbit takes place in a world of the author’s own creation—complete with its own history, language, geography, and mythology—much of the narrative is devoted to incidental descriptions of the places, people, and things that Bilbo encounters. As a result, Middle-Earth emerges as a finely detailed reality with a convincing visual presence and its own unique atmosphere. Taking the reader through this world is one of the primary considerations of the novel, and a great part of Tolkien’s literary ingenuity is devoted to making Middle-Earth seem as real as possible. For many readers, experiencing Middle-Earth as a self-contained whole is probably the most striking aspect of reading The Hobbit.

Throughout epic literature, swords with names and lineages are the marks of great heroes. One of the most famous examples is King Arthur’s sword, Excalibur. The swords named Orcrist and Glamdring that Thorin and Gandalf win from the trolls symbolize their heroic deeds. Bilbo’s decision to name his short sword Sting after killing the spider is a major turning point in his quest—it symbolizes his bravery and initiative, and presages his transformation into a hero.

Though the thematic importance of hobbits is highly debatable, Tolkien himself acknowledged that the nature of hobbits was based on the rural, middle-class English people among whom he lived. This symbol enables Tolkien to explore the contrast between ancient and modern worldviews as the modern-minded Bilbo travels the ancient world of Middle-Earth.