When we think of Sherlock Holmes we think of gas-lamps and fog and other stereotypically Victorian London things. In this case, the stereotypes are pretty accurate, but they don't tell the whole story. The Sherlock Holmes stories are like quintessentially Victorian English tales, which means that they are great little representations of Victorian England. But it's important to know exactly what we mean by Victorian and English. We're going to start big and work our way inward here.
First off, we have the "when" part of the setting: the 1890s or the Late Victorian era. Victorian is one of those terms that get tossed around a lot and can mean a lot of different things. We here at Shmoop like being specific, so we'll be talking about the Late Victorian period for the setting. People who study English literature and history often say that the Victorian period lasted the length of Queen Victoria's reign, 1837-1901. Which is a really long time. The Late Victorian period lasted from around 1870 until the end of the nineteenth century. There are a lot of reasons this period is distinguished as "late" Victorian, aside from the obvious date reasons. These reasons include new technologies, changing fashions, political situations, new types of literature, etc. that set this period apart from the earlier parts of Queen Victoria's reign.
The 1890s are unique for lots of reasons. Technology and culture is one of them. In this period, a lot of new technologies changed the way people lived. Bicycles were the new rage; electric lights were becoming more common; automobiles made their first appearance; the London subway system was growing; trains were faster; telegraphs made world-wide communication easier. We see evidence of a lot of these technological advancements in the Sherlock Holmes stories. Holmes and Watson ride the train all the time. Bicycles play a huge role in a number of stories. And Holmes and Watson also frequently read the newspaper, which changed a lot with the arrival of the telegraph. News was much faster and easier to get in the 1890s.
A lot of things were changing in the 1890s, which led to a lot of excitement and a lot of anxiety. This atmosphere is reflected in the Sherlock Holmes stories, particularly through the role of foreigners. (You can read more about this in the theme section on "Foreignness and the 'Other.'") The British Empire was huge, and growing, in this period. So even though a lot of the action in these stories occurs in London, these stories have a world-wide scope. A lot of the criminals Holmes deals with come from various places in the British Empire – South Africa, India, Australia, etc. London especially was an international hub in this era. Lots of people were anxious about the number of foreign people pouring into London and the crime rates of the city. Holmes, as a sort of ultimate crime-stopper, helped to combat that anxiety.
We've mentioned London, but it's important to note that lots of these stories are set in other places in England. Crime isn't just limited to the big city here, and this reflects the changing world of the 1890s. Communication and transportation were connecting far off places and the peaceful English countryside wasn't immune from the city anymore. It's also important to note that smaller towns and the English countryside reflected London in lots of ways. In the countryside, as in London, Holmes and Watson encounter rich people and poor people, natives and foreigners, etc.
London is arguably the main setting of the Holmes stories. But the city isn't as stereotypically Victorian as popular conceptions of Holmes suggest. True, Holmes and Watson encounter fog, gas-lamps, horse-drawn carriages, and "bobbies," or the London Metropolitan Police, in these stories. But they also live and work in a city with lots of social classes, nationalities, crime, confusion, and layers. Watson sums up London a few times. Good job, Watson.
[T]he gleam of street-lamps flashed [....] I knew not what wild beat we were about to hunt down in the dark jungle of criminal London [....] (Empty House.36)
Watson often compares London to a "jungle," which ties the city to the idea of Britain as a gigantic empire, containing deserts, and forests, and "jungles," in some interesting ways. London, the international city, isn't cut-off from the world here. This idea of "criminal" London is also important since it implies that there are a lot of different Londons, so to speak.
In rapid succession we passed through the fringe of fashionable London, hotel London, theatrical London, literary London, commercial London, and, finally, maritime London, till we came to a riverside city of a hundred thousand souls, where the tenement houses swelter and reek with the outcasts of Europe. (Six Napoleons.83)
There are a ton of different sections of London here that combine to make a gigantic, complex whole. It's notable that Watson refers to a "riverside city" where poor immigrants live, describing it as a sort of city within the larger city of London (Six Napoleons.83). The middle-class Holmes and Watson cut across class, and geographic, boundaries in their investigations.
But they always return home to 221b Baker Street. Stories often start from Baker Street as well. Holmes's iconic Baker Street pad acts as a haven from the outside world, a stage where exciting criminal investigations are jump-started, and an extension of Holmes's character.
My friend's temper had not improved since he had been deprived of the congenial surroundings of Baker Street. Without his scrapbooks, his chemicals, and his homely untidiness, he was an uncomfortable man. (Three Students.6)
Even though he's an über detective, Holmes is also a bit of a homebody. His bachelor pad with Watson might be kind of weird, functioning as a sort of science lab/police station. But it is also often described in cozy, domestic terms. It's a "congenial" (Three Students.6), or friendly and homey place, which helps it to stand out some from the international and criminal chaos of the other places featured in the book.