Hands down, this is Victor Hugo's most known and commercially successful book. It's a romantic slash gothic novel, set in France (Paris, to be exact) in 1482. The Hunchback of Notre-Dame was published in 1831 and instantly became an international phenomenon. The story is focused around the world-famous Notre Dame Cathedral, the country's pride and joy.
Fun fact: Shoberl, the man who translated Hugo's novel into English, named it The Hunchback because Gothic novels used to be the most popular ones in the UK at that time. The author started working on his monumental novel in 1829 and wanted to make folks appreciate the Gothic architecture that was slowly, but steadily being replaced by the new, more advanced buildings in France and the rest of the world.
Furthermore, some of the structures that were decided to be left Gothic were "modernized" and fixed by parts of buildings of the then-contemporary styles, which made Hugo even more disappointed: the glass panels of Notre-Dame were switched with white glass that lets in more sunlight into the building. The author's love for the Gothic style is exactly why the book is filled with tons of descriptions of materials, different construction techniques, et cetera, et cetera.
Still, it holds great value for the historians, as it represents a certain era in history and allows the modern-day readers to learn about the "ins and outs" of France in the 19th century. Esmeralda, a gypsy woman, enchants numerous men, including Frollo, who can't pick a "side" between his lust for the seductive lady and the rules of the Cathedral. She's the main character of The Hunchback of Notre-Dame - literally and figuratively.