Fiction is imaginary, so who needs to do research? OK, maybe a little basic stuff about chemistry, or rocketry, or a little biology so your alien creatures are semi-plausible if you are not a good enough writer to use pure handwavium and get away with it (or even if you are). But that’s about it, right?
I wish. I’d get to read a lot more science fiction and fantasy if I didn’t need to do so much reading for my writing, especially for the Colplatschki series. To give you a peek behind the scenes, here are some of the books that have been used for background, in no set order:
Andrew Wheatcroft, The Enemy at the Gate
John Stoye The Siege of Vienna
Frank Tallett War and Society in Early Modern Europe
Rhodes Wilson Ottoman Warfare
Peter S. Wilson (no relation) The Thirty Years War (highly recommend but is a tome)
Lauro Martines Furies
Geoffrey Parker Global Crisis (and a lot of his earlier works over the years. If you do 17th Century, you have to read Parker)
R.J.W. Evens Rudolph II and His World
A. Trevor Hodge Roman Aqueducts and Water Systems
Stuart Clark The Sun Kings (about Richard Carrington and solar astronomy)
G.I. Brown Explosives: History with a Bang (highly recommend, fun book)
And a couple more on Renaissance and Early Modern warfare, plus Castiglione’s Book of the Courtier and histories of the Habsburgs, of Slovakia, Hungary, Louis XIV’s wars, an mammoth collection of essays about technology of the classical world, and several works on the care and training of mules. There’s a similar stack of WWI stuff lurking just out of sight, or en-route as they are released this summer. Most of the medical history I’ve absorbed from various sources over the years.
I may be reading as much as I did for my dissertation, with fewer technical works and more general overview histories. Will all of this show up in the books? No. But they provide the background and color I need for the worlds I create. And they’ve saved me from a few glaring errors, such as travel time (a lot longer than you would think) and technology (coarser gunpowder is better for artillery, finer grind for small arms.)