So my definition post on Steampunk was well-received enough that I decided to turn it into an occasional series chronicling the development of a steampunk world. Specifically the one in CALLARION AT NIGHT, my in-revisions WIP.
Steampunk, as it was originally used, forced writers to compose their tales in an alternate version of Victorian London (or any city of that era, though London was most common) because that's when steam was really King of the World. H.G. Wells and Jules Verne were the prototypes for these writers, with their advanced science and gleaming crystalline, copper, and brass machinery. The other concession made sometimes involved the theory that some form of computing power existed -- whether it was Babbage's Analytical Engine (THE DIFFERENCE ENGINE by William Gibson and Bruce Sterling) or something different.
Then a subset of this fiction started happening where the time period was either far-future after a devastating war (FITZPATRICK'S WAR by Theodore Judson) or, as in my WIP, a fantasy world that has little to no relation to our own. These secondary stories sometimes eschewed the dystopian elements of the prototypical steampunk works, instead weaving steam technology into fantasy settings while still potentially maintaining the ability to have magic (an example escapes me right now).
I'll close this entry before it gets too long with a brief list of some subject areas I researched to craft the world of CALLARION AT NIGHT:
Slums of Victorian London
19th Century British and American weapons
19th Century consumer goods
19th Century Russian culture
Early armored vehicles
Capsaicin (the chemical in chili peppers)
Odd list, yes I know, but I promise it will make some sort of sense eventually. I hope so at least.