Riven, a novel in which space wizards attempt to prevent the apocalypse by splitting the sun (not really. but eventually?), launches today. Like most fantasy or science fiction, it occupies a world that’s to some degree built upon reality, ideas that came before, and bunches of frenetic hallucinating that resulted in the setting for the book and its coming sequels.
Read up on authors that write this stuff and you’ll find multitudes of world-building strategies. There’s the Tolkien dissertation-level deep dive wherein you come up with whole languages, thousands of years of history, and potentially even unexpected books through the creation of your world. You can set the story in today’s world, perhaps with an added (but believable) dose of secret spy organizations.
You can cut between; taking bits and pieces of mythologies, themes, and places to create a composite that builds a “believable” world without the all-consuming effort of creating everything from scratch. Riven is most like this – taking pieces from the real world (Chicago), mythologies (the afterlife and various presentations of it), and existing setting/theme ideas (steampunk/dark fantasy).
With Wild Nines, I used minimal real life “places”, but leaned on somewhat plausible future technologies. The aforementioned space wizards didn’t make an appearance. People didn’t teleport or wave their hands to make miracles happen at will.
Ultimately, the goal of any setting is to support the story. The world has to make your plot plausible – in Riven, the main character often uses a “lash”, a version of a whip, which wouldn’t make so much sense if I’d set the book in the far future. Why would my characters know how to use medieval-style weapons if everything else leveraged laser cannons ala Star Wars?
Creating an appropriate world can also help you eliminate questions that might otherwise create plot holes. Riven, to a degree, is about how humanity deals with the prospect of spirits returning to the real world. If this was an intergalactic sci-fi story, I’d need to deal with aliens, and how a “world of the dead” appears to all of these different species. This isn’t necessarily a poor idea for a story, but it’s not the one I’m trying to tell here.
It’s “supporting the story” that I focus on when considering the setting – I think most stories start off as a sentence or two of an idea: “What if a billionaire was a crime fighter in secret?” “What happens if an evil being depends on a ring to exist?” “What if a band of little blue people were harassed by an inept wizard?”
Yeah, even The Smurfs had to design the setting of their show in line with the needs of that idea. From that sentence, you can start to design a world around your story. A wizard generally demands magic, and if your scope involves “a band”, then you likely don’t need giant continents and countries. Keep the scope in line.
Already, though, The Smurfs has a feel. From there, the setting can grow to answer critical questions about how the little band lives. How do they eat? What sort of homes do they have, etc?
You can, of course, go the other way and start with a setting. The main reason I don’t is because you can wind up throwing out sections of a world that don’t apply, or that are no longer valid once you settle into your idea. You can, for example, look at the Lord of the Rings and all of the various elements of Middle Earth that have no impact on the story. Tolkien wrote other books set in the same world, but many pieces of that setting are described only in passing, or in passages that have little impact on the actual narrative (Tom Bombadil’s section in Fellowship of the Ring, for example).
Obviously, at four novels in, there’s an asterisk to what I can claim as “the best way” to build a book’s world, and I’d probably look askance at anyone who makes such a claim (and you don’t want my askance glance; it’s terrifying). I can, though, say that so far building the setting from the story has worked better than the other way around, and until I get to a point where I can spend my days custom-designing dragons and their treasure hoards, that’s what I’ll keep doing.