What are the significant historical events of 1880 to 1925 that form the contextual setting of The Sign of Four by Arthur Conan Doyle? Among the...

The Sign Of Four was written against the backdrop of the Sepoy Rebellion or Indian Mutiny of 1857.

By the 1850s, the East Indian Company ruled India on Britain's behalf. In this system, the Sepoys were incredibly fierce and loyal soldiers hired by the English to maintain order at trading posts and reservations. Despite their loyalty, these proud Sepoys were driven to anger and despair at the daily abuses perpetrated upon the Indian people by their English occupiers. As an example, when a local leader died without an heir to continue his rule, the British swooped in to annex the region, without consultation with the local populace. The Sepoys were also incensed by what they saw as an encroaching Christian influence in their country. They felt deeply violated by acts of supreme inconsideration on the part of the British in installing Christian missions and schools in India.

Despite these abuses, the Sepoys didn't mutiny until a rumor took hold upon an unsuspecting public. Accordingly, the British had resorted to using pig and cow grease in the cartridges of rifles that were largely used by the Sepoys. If true, this was considered an outrage. The mutiny started on March 29, 1857, when Mangal Pandey, a Sepoy soldier, refused to use the new rifles. In defiance, he shot an English lieutenant and sergeant-major. This incident fueled many more atrocities before the situation was brought under control by the English. Both sides resorted to brutal violence to achieve victory; yet, not every atrocity on the Indian side was committed by the Sepoys alone. During the Cawnpore massacre (this is mentioned in Jonathan Small's story in Chapter 12), many Sepoys refused to participate in the killing of more than 200 English women, children, and infants. As a result, butchers were brought in by local leaders to cut down the defenseless women and children.

So, why is this background important? In the story, we are given glimpses of the prevailing British opinion about Indians. The imperialist attitude (that Indians were savages who needed to be civilized) can be seen in Holmes' descriptions of various footprints belonging to that of the darker races:

"A savage!" I exclaimed. "Perhaps one of those Indians who were the associates of Jonathan Small."

"Hardly that,"... the remarkable character of the footmarks caused me to reconsider my views. Some of the inhabitants of the Indian Peninsula are small men, but none could have left such marks as that. The Hindoo proper has long and thin feet. The sandal-wearing Mohammedan has the great toe well separated from the others, because the thong is commonly passed between. These little darts, too, could only be shot in one way. They are from a blow-pipe. Now, then, where are we to find our savage?"

And, here again, we see Holmes educating Watson on the savagery of the aborigines of the Andaman Islands. He also tells Watson that some of the smallest races of men may invariably be other darker-skinned peoples such as the Bushmen of Africa, the Digger Indians of America, and the Terra del Fuegians:

'They are naturally hideous, having large, misshapen heads, small, fierce eyes, and distorted features. Their feet and hands, however, are remarkably small. So intractable and fierce are they that all the efforts of the British official have failed to win them over in any degree. They have always been a terror to shipwrecked crews, braining the survivors with their stone-headed clubs, or shooting them with their poisoned arrows. These massacres are invariably concluded by a cannibal feast.'

In the story, Jonathan Small tells of the Sepoy Mutiny in Chapter 12; he describes India being over-run by 'two hundred thousand black devils let loose,' and he also admits his part in making a pact with two Sepoys (Mahomet Singh and Abdullah Khan) and a third, Dost Akbar, in order to save his life during the Mutiny.

The rest of the story is continued in the chapter, of course; however, we can see that this historical background reinforces the English mentality of Indians as inferior savages, and of India as a corrupting influence upon the British psyche. It is no coincidence that every chief player in the Agra treasure incident has been consumed by suspicion and greed.

Another anecdote owing to historical origins in the story would be the infamous 'cocaine discussion' in Chapter 1. In the 19th century, England became a successful global trafficker of opium. From India, opium was trafficked to China. Interestingly, cocaine in 19th Century England was widely used as a mental stimulant. You can read Holmes' rationale of his use of cocaine to Watson in Chapter 1:

I find it, however, so transcendently stimulating and clarifying to the mind that its secondary action is a matter of small moment.

For more, please read about Victorian Drug Use.

I hope that what I have written proves useful for your project. Good luck!