Tons of fluff for Pathfinder. Most of it focused on a half of a continent, in an area called the Inner Sea. There's lots of other areas of the world that aren't really touched on, and even alien planets. Literally thousands of years of history made up.
All you really need to know are the core races and core deities. The races are Humans, Dwarves, Elves, Gnomes, Halflings, Half-Orcs and -Elves. They are the most populous races, with Humans being the forerunner by far. The world is a clusterfuck of mini-factions, guilds, and nations.
It's recovering after a series of apocalyptic events, including a number of massive fuck-off hurricanes larger than most countries, with one permanent one to serve as a momento for everyone, called the Eye of Abendego.
An alien capital ship crashing into the world and staying mostly intact after the crash, with its internal factories still churning out robotic murder machines and sapient Androids, which are playable races, and somehow have a soul because nanomachines, son.
And lets not forget the literal hole to the Abyss in the northern part of the world, now known as the Worldwound, that continually spouts out demons.
Also, the patron God of humanity, Aroden, may or may not have died. He's not answering any prayers, and has since been replaced by a Paladin of his. Who ascended to deity status the same way he did. I'm sure that will bode well in the future. Actually, a few mortals stole his idea. There are many ascended mortals, from a Monk who meditated until he became too swole for this world, to a pirate-queen who got bored with normal targets, and started swashbuckling her way through the different planes instead, reaching deific powers along the way.
There's more, but these come to mind as the more major events.