Much of Doyle’s popularity today stems from his vivid description of late-Victorian London. From the defeat of Napoleon in 1815 to the start of World War I in 1914, Britain was the dominant military power in the world. As a result, London was both the world’s largest city and the center of the most extensive and powerful empire in history by the end of the nineteenth century. Victorian London was also a city of mystery: a place of dark fogs, horse-drawn carriages, and Jack the Ripper. In other words, even though London at the end of the nineteenth century was the de facto capital of the world, Londoners were still deeply interested in their city’s dark undercurrents. Readers today find this mix of power and mystery fascinating and share with Doyle’s contemporaries a love for the way in which the intellect of Sherlock Holmes cuts through the shadows, illuminating the darkness with pure reason.