The project I'm working on now--tentatively titled "Violence In The Nympharium"--for LotFP has me looking pretty hard at the 17th Century because it involves a lot of locations and time travel as a basic element. It's going to be impossible to do without actually paying attention, much as I do hate paying attention.
So the basic thing is: wtf is the 17th century?
Well, basically: pirates.
That is, it's the golden age of piracy and most other members of the adventuring class (like musketeers) look kind of piratey--at least in Europe. Even on land people had big feathers on their hats and skinny swords. Boats looked cool, including galleons and the sleek, triangular-rigged xebecs.
The visual artists were getting as good at getting materials to do what they wanted as they ever would be, it was the Baroque era: Velasquez, Vermeer, Willem Kalf, Bernini, Finelli, Rembrandt. The British, as always, were a little behind in painting...
...but they did have the tail end of Shakespeare and then Milton writing Paradise Lost.
Louis XIV was in France being as fancy as fancy has ever been, tumblr fave Julie d'Aubigny was being about as badass a bisexual opera singer/duellist/nunfucker/arsonist as you could ever ask for, and most of the famous occultists are French. The Lesser Key of Solomon--the most well-known grimoire--is compiled.
Western Europe is as Europey as it is ever going to get right now. Go back much further and its barbarism and armor and nobody even wears wigs, go forward and suddenly people start being impressed by the industriousness of Americans and having real pants.
The big downside is the whole Reformation thing which makes reading history around this time really really boring. Like you get ahold of something that sounds pretty exciting like The Defenestration of Prague and look it up and it's Catholic this and Protestant that and before you know it you're asleep between your Norman Davies and your Geoffrey Parker.
In India style was--so far as I can tell--within a stone's throw of the extremely stylish late medieval as exemplified in the paintings of Bihzad. You could still see war elephants, which is dope, plus a lot of bright fabrics, baggy pants, and pointy shoes. The thugee cult of assassins still roamed the land, though, contra Indiana Jones, not in sinister matching robes -sadface-.
Likewise looking sharp were North Africa and much of the Islamic world. The Ottoman turks were near the maximum extent of their power with very big turbans. They probably have the most D&Dable architecture around now, with lots of Islamic cultures producing big flat-sided, ornate stone buildings with a lot of geometry and niches and taking up a lot of space (as opposed to Europe where--under the appalling influence of humanism--even the grandest public buildings have largely abandoned otherworldly monumentality to take on the fluted, pointy-roofed, comfortably-grooved appearance we play games to not have to think about).
Parts of northern Africa--like Coptic Ethiopia--are still operating out of cool medieval buildings, like castles and stuff.
Japan is perfect right about now: the Tokugawa shogunate has just begun, samurai are everywhere and there's still ninjas. (The big ninja book was written during this period.) Also Japan had English, Spanish and Portuguese traders reporting back home.
In southeast asia they're in the very early stages of colonialism, and the locals are still building mindblowing temples and palaces.
In Russia there's a lot of peasant riots and sashes and funny fur hats and a "Time of Troubles". So kind of the usual.
The non-Muslim, non-Christian parts of Africa are very poorly recorded around this time and in many kingdoms the 17th century still counts as "legendary". This is after the fall of the city of Great Zimbabwe which means something like "big stone house" and would have been eminently dungeonable (sigh) but there are sites like Kami which are like little Zimbabwes. A lot of guesswork surrounds what people there might've worn, lived in, or killed each other with in these areas and a lot of sources seem to just throw up their hands when it comes to magic and folk beliefs due to the wide variety. The most interesting and non-boring-stereotype-reinforcing path seems to be looking at current belief and working back off that. So like digging out the Robert Farris Thompson again.
China has kind of the opposite problem: so much history I have real trouble keeping it straight. We are in the Ming-Qing transition, but the general rule with China seems to be (1) if you can kill someone with it they've tried it from rockets to trained cheetahs and (2) all previous eras of Chinese history exist in China at all times.
The Americas have a lot of feathers and pilgrim hats going on and can fuck off. I'm not doing it and Australia seems to be mostly Dutch people poking at it while native Australians ignore or kill them.
Experience tells me that lots of people who read this blog are hard-eyed library-devouring history types with actual degrees to whom this will all seem very basic, but if you're reading and can think of some book, resource or image that makes some underappreciated part of the 17th C seem interesting, we're all ears.