Le Chevalier C. Auguste Dupin is a fictional detective created by Edgar Allan Poe. Dupin made his first appearance in Poe's "The Murders in the Rue Morgue" (1841), widely considered the first detective fiction story. He reappears in "The Mystery of Marie Rogêt" (1842) and "The Purloined Letter" (1844).

Dupin is not a professional detective and his motivations for solving the mysteries throughout the three stories change. Using what Poe termed "ratiocination", Dupin combines his considerable intellect with creative imagination, even putting himself in the mind of the criminal. His talents are strong enough that he appears able to read the mind of his companion, the unnamed narrator of all three stories.

Poe created the Dupin character before the word detective had been coined. The character laid the groundwork for fictitious detectives to come, including Sherlock Holmes, and established most of the common elements of the detective fiction genre.

Dupin is from what was once a wealthy family, but "by a variety of untoward events" has been reduced to more humble circumstances, and contents himself only with the basic necessities of life. He now lives in Paris with his close friend, the anonymous narrator of the stories. The two met by accident while both were searching for "the same rare and very remarkable volume" in an obscure library. This scene, the two characters searching for a hidden text, serves as a metaphor for detection. They promptly move to an old manor located in Faubourg Saint Germain. For hobbies, Dupin is "fond" of enigmas, conundrums, and hieroglyphics. He bears the title Chevalier, meaning that he is a knight in the Légion d'honneur. Dupin shares some features with the later gentleman detective, a character type that became common in the Golden Age of Detective Fiction.^{[citation needed]} He is acquainted with police prefect "G", who appears in all three stories seeking his counsel.

Edgar Allan Poe (born Edgar Poe; January 19, 1809 – October 7, 1849) was an American author, poet, editor and literary critic, considered part of the American Romantic Movement. Best known for his tales of mystery and the macabre, Poe was one of the earliest American practitioners of the short story and is considered the inventor of the detective fiction genre. He is further credited with contributing to the emerging genre of science fiction. He was the first well-known American writer to try to earn a living through writing alone, resulting in a financially difficult life and career.

He was born as Edgar Poe in Boston, Massachusetts; he was orphaned young when his mother died shortly after his father abandoned the family. Poe was taken in by John and Frances Allan, of Richmond, Virginia, but they never formally adopted him. He attended the University of Virginia for one semester but left due to lack of money. After enlisting in the Army and later failing as an officer's cadet at West Point, Poe parted ways with the Allans. His publishing career began humbly, with an anonymous collection of poems, Tamerlane and Other Poems (1827), credited only to "a Bostonian".