One thing writers tend to do is read voraciously, and omnivorously. I stumbled on Brian Fagan’s various archaeology/history books a while back (The Little Ice Age: How Climate Made History 1300-1850 being one of the more recent ones) and ever since I’ve gone after all the books I could get hold of on environmental history. After all, if you’re trying to worldbuild, cultures and politics may come and go, but the environment people have deal with is a constant factor. It shapes their choices, decides a lot of their options, gives various combat bonuses and penalties. Try a long-distance run with a heavy pack in a New England style autumn, you’re likely to be pleasantly warm; the same weight, run, and time of year on the Gulf Coast may have you prostrate of heat stroke. Festus Hagen of Gunsmoke is an expert with a rifle because that weapon had a distinct advantage in the forested Ozarks he grew up in, where you can often see a surprising distance. While Marshal Dillon is far better than him with a revolver, a weapon far more handy at close range; on the undulating ancient seabed that makes the Great Plains, someone can be thirty feet away and downright invisible.
Read enough books, and you start picking up common threads from a bunch of different sources – things that make you go hmm. Especially when you were reading up on what you thought was a different aspect of the world entirely, and something oddly familiar pops up and waves. (Some of the best story fodder, that.)
I’ve been reading up on Korean history for a potential fantasy story setting, specifically Joseon, and a lot of that revolves around their dealings with China; first the Ming Dynasty, then the Qing when the Manchus took over.
The timing of famines in Korea, the Ming Dynasty collapse, and the Manchus busting loose and making trouble all over the place seemed to ring a bell. So I checked dates.
“Oh. Bleep. 1620s-1650s… the height of the Little Ice Age.”
…If you’re not familiar with the Little Ice Age, I strongly suggest checking out the Wikipedia article, and maybe reading through some of the sources. (I’m currently going through the Kindle sample of Geoffrey Parker’s Global Crisis: War, Climate Change and Catastrophe in the Seventeenth Century. It’s a lot.)
This info makes a lot of the crazy going on during that period of history make a lot more sense. If your town’s been farming the same way for a hundred years, and suddenly there’s storms all over the place, frosts weeks earlier than they ever have been and weeks later, crop failures everywhere, people dying or getting run over by the latest marauding army because some noble smelled weakness across the border….
Yeah. People went nuts. Not everyone, but more than enough. And royals saw things as divine disfavor to their enemies, meaning perfect times to attack, meaning they needed ever more taxes to support armies and navies at the exact time there were years there were no crops–
You can see why people might take a leap of faith and move across an entire ocean just for the chance to get clear of some of the madness.
…And now I can’t help but wonder how many of the people poking Eric Flint’s 1632 shared ‘verse understand what the weather was like at the time. Or what it led to people doing, and trying to do.
Circling back to why I was originally reading up on this… First, I have concluded I need to get a copy to read the rest of Global Crisis; it has far more info on what was happening in Asia than the Fagan book. (Which is fair, it’s a much bigger book.) Second-
Second, I suspect the poor isekai’d character I have in mind, once he learns about what time period this world is in, has a justifiable freakout. Because monsters? The least of your problems….