1876 illustration from Murder In the Rue Morgue
Trying to figure out what constitutes the earliest mystery novel can be like trying to dig a hole in the sand: no matter how deeply you go, you never seem to reach the bottom. Part of the problem is, what does one really mean by "mystery novel"? Detective fiction, crime fiction, a novel in which a mystery is solved? Depending on how you define the genre, early mysteries might include Oedipus Rex by Sophocles, "The Three Apples" from Arabian Nights, or Chinese gong an stories.
However, mystery novels as most of us understand them today more or less started in the 19th century. Some very early examples:
- Mademoiselle de Scuderi by ETA Hoffmann (1819)--A poetess discovers who is murdering people and stealing their jewelry in this Louis XIV-era novella. However, Mlle Scuderi doesn't exactly solve the murders, so whether or not this can be really be called a detective novel is debatable. [available to read online here]
- The Rector of Veilbye by Steen Steensen Blicher (1829)--A Danish novella based on a true murder case. [can be found in this mystery compendium at Project Gutenberg|Librivox]
- Murders in the Rue Morgue by Edgar Allan Poe (1841)--This is usually considered THE very first detective mystery. Poe established the formula for the mystery genre, as well as created a memorable detective, C. Auguste Dupin (who was based on Eugène François Vidocq, real-life director of the Sûreté Nationale, the founder of the first private detective agency, and the father of modern criminology as well as the French police). Dupin also appeared in The Mystery of Marie Rogêt and The Purloined Letter. However, since these stories are short, can they really be called "novels"? [Project Gutenberg|Librivox]
- Notting Hill Mystery by Charles Felix (1862)--This serialized mystery appears to be the first British detective novel. It centers around an insurance investigator who believes a baron killed his wife. Fun fact: Daphne du Maurier's grandfather illustrated the story. [available to read in original serialized format at Internet Archive]
- Monsieur Lecoq by Emile Gaboriau (1868)--This is often cited as the first French mystery novel, with a detective who was also based on Vidocq. Like his real-life counterpart, Lecoq is adept at disguises and applies the scientific method in unraveling crimes. [Project Gutenberg|Librivox]
- The Woman in White (1858) and The Moonstone (1868) by Wilkie Collins--Although more properly classified as a sensational novel, in my opinion, The Woman in White has a central mystery and is usually cited as one of the first British mysteries. The Moonstone is more of a proper mystery and contains plot elements like red herrings, a locked room, false suspects, and a professional investigator. TS Eliot called it, "the first, the longest, and the best of modern English detective novels," and Dorothy L. Sayers called it, "probably the very finest detective story ever written." [Project Gutenberg|Librivox]
- The Leavenworth Case by Anna Katherine Green (1878)--As far as I've been able to find, this is the first detective novel by a female writer. The detective, a Mr. Gryce, attempts to figure out who shot the wealthy Mr. Leavenworth in the back of the head. [Project Gutenberg|GirleBooks|Librivox]