A Study in Scarlet is an early example of detective fiction. The modern detective fiction genre—in which an investigator or detective investigates a crime, usually a murder, and uses their keen observational skills to reconstruct the crime and identify its perpetrator—arose in the mid-19th century, shortly after the Industrial Revolution.
It is possible that the genre arose in response to the mass migration of people from the countryside to cities as a result of new factories being built in the cities. Whereas previously most people would have lived in small towns where they knew their neighbors, when people started moving to cities, they suddenly lived in close proximity to others that they knew nothing about; for all they knew, their next-door neighbor could be a murderer. This heightened anxiety about crime—as well as an actual rise in criminal activity—led to the development of the first police forces and the publication of the first detective fiction in the early 19th century.
Many regard Edgar Allan Poe’s 1841 story “The Murders in the Rue Morgue,” featuring the eccentric and brilliant C. Auguste Dupin, as the first modern detective story in English. A Study in Scarlet was heavily inspired by Poe’s story and bears many plot similarities. Like A Study in Scarlet, "The Murders in the Rue Morgue" is told from the first-person point of view of Dupin’s friend and roommate, who greatly admires Dupin’s intelligence and accompanies him as he uses his analytical and observational skills to solve a murder (not unlike the dynamic between Watson and Sherlock). Doyle acknowledges that he was inspired by Poe by directly alluding to Dupin in Part 1, Chapter 2 of A Study in Scarlet:
“It is simple enough as you explain it,” [Watson] said, smiling. “You remind me of Edgar Allan Poe’s Dupin. I had no idea that such individuals did exist outside of stories.”
Doyle once described Poe as the inventor of modern detective fiction, saying about his work, that “Each [of his detective stories] is a root from which a whole literature has developed…Where was the detective story before Poe breathed the breath of life into it?” Indeed, Poe was so early to the genre that the word “detective” hadn’t been used yet in English when “The Murders in the Rue Morgue” was published in 1841. Rather than using the term “detective fiction,” he described his Dupin stories as tales of “ratiocination,” which referred to a process by which an investigator combined logic, intuition, and observation to ascertain the truth.
Most detective fiction, like A Study in Scarlet, took place in cities, often focusing on poor, dilapidated neighborhoods and poorly lit city streets at night. This reflects the heightened anxiety about urban crime in the 19th century. Detective fiction served both to explore and to soothe these anxieties with logical solutions and explanations. The detective figure in these stories, like Sherlock Holmes, often serves to bring the light of truth to the terror and confusion of darkened city streets, explaining for readers what possible motivations and rationales criminals might have for committing crimes.
