We're accustomed to seeing old photographs in black and white because that was the simplest and least expensive manner of making them for many years. Taking color pictures was possible, but it was complicated and expensive. If you happened to be a wealthy chemist who got the gift of a special railroad car with its own darkroom from your kinsman Tsar Nicholas II, then you could probably handle it.
Which Sergey Prokudin-Gorskii did, taking color photos of life in many of the most far-flung areas of Russia in the years leading up to World War I and the later Bolshevik revolution. Prokudin-Gorksii was impressed by the many different kinds of people he met in his enormous country, and wanted to use the fascinating technology of color photography to teach children about their diverse homeland. Unfortunately, said WWI intervened, Nicholas made some disastrous decisions that set the stage for the Communist takeover and Prokudin-Gorskii got the heck out before he could be comradized.
The variety of cultures he found is indeed fascinating. We're accustomed to thinking of Russia as gray, cold and oppressed -- and thanks to Vladimir Putin, that last one is making a comeback -- but that's just what you might call "European Russia." As the photo above shows, the vast nation included an astonishing variety of peoples and cultures, and it still does. More of Prokudin-Gorskii's photos are available here, at the Library of Congress.