Historical Fiction, Romanticism, Tragedy
Historical Fiction
Victor Hugo, one of the most famous writers of the nineteenth century, rarely ever wrote about the nineteenth century. He was all about times past. That makes his books doubly complicated: they're not just about the past; they're about the distant past from the point of view of a more recent past. To get what Hugo is up to here, we have to understand a little bit about both the Middle Ages and the nineteenth century.
Now, one of the things that makes historical fiction so great is that it tends to use events set in the past to make comments about things that are still relevant—maybe the political situation of the present, maybe laws or customs that still endure but in a different form, or maybe just unchanging human nature.
Hugo may be a Middle Ages connoisseur, and there may be all kinds of cool details about the Middle Ages all over The Hunchback of Notre-Dame, but the novel is actually more concerned with the France of Hugo's era than France in 1482. That's why we get all those weird asides about guillotines, state power, and the Bastille, all of which were more or less contemporary concerns for Hugo (though we should also add that the French Revolution came about fifty years before Hugo wrote this novel).
Romanticism
Speaking of historical eras, The Hunchback was published in 1831, which puts it smack-dab in the middle of the Romantic period (the first half of the nineteenth century). No, it's not that people were more lovey-dovey then. It's that writers were more focused on emotion and people's internal lives than on, say, reason or scientific facts.
In English literature, for example, Romanticism is associated with poets like Lord Byron, Keats, Shelley (both of them), Coleridge, and Wordsworth. These writers wanted to create art where the emphasis was on emotion, the individual, and natural beauty.
Now, just because something was written during the Romantic period does mean that it's necessarily Romantic. The Hunchback of Notre-Dame, though, fits the bill in a lot of ways. First of all, it romanticizes a distant past by making it pretty and dramatic. Sure, the past as presented in the novel isn't always that pretty, but the narrator spends a whole book complaining about how contemporary Paris lacks that certain je ne sais quoi it used to have during the Middle Ages.
Second, the entire story centers on the lives of individuals—and, more importantly, on their emotional responses. That's all very romantic. Hugo does eventually go on to talk about grand themes and events (also Romantic themes), but he does so throughthe personal experiences of these individuals.
Tragedy
Last but not least, The Hunchback of Notre-Dame is a tragedy. The easiest way to recognize this is by counting the number of corpses you have by the last page.
Yeah, it's a lot.
All right, a high body count doesn't necessarily make something a tragedy (though it helps). What really makes this novel a tragedy is that pesky hand of fate doing its thing all over the place. Hugo brings up fate right away in the Author's Preface, and the theme never really goes away: it sets the tone for the whole novel.
As the characters get more and more wrapped up in each other's' lives, we see them moving unstoppably toward some sort of climax. We get a sense that not everyone is going to come out of this novel in great shape. In classical Greek drama, tragedy involves the inevitable fall of a great character, and fate in The Hunchback gives all of the events in the novel that same sense of an inevitable catastrophe.
But there is a little play on this genre at the end of the novel. By Shakespearean standards, tragedies end in death, and comedies end in marriages. Now, the last two chapters of The Hunchback are called "The Marriage of Captain Phœbus" and "The Marriage of Quasimodo." What's up with that?
Neither of these are particularly happy marriages—the narrator even tells us that Phœbus himself "came to a tragic end" (XI.III.5) in marriage (we're supposed to get a chuckle out of that), and Quasimodo's marriage involves two corpses—but they do provide an ending that focuses, in a way, at least partly on hope, rather than just on death and more death. Fate, though it has wreaked a lot of havoc, in the end brings Quasimodo and Esmeralda together, and we guess that is something.