Medieval Stasis
Medieval Stasis describes the state of essentially all fantasy worlds that are not steampunk. As the title implies, most fantasy worlds are stuck at a technological level roughly equivalent to most of Europe in the year 1000.
On the one hand, it would superficially appear that most of Europe was stuck in a developmental rut between the fall of the Roman Empire and the start of the early modern era in the 1400s, wherein the creation of centralized nation-states and the end of feudalism (eventually) led to a blossoming of science. And indeed, technological development back then was much slower and a fair bit was lost . However, even throughout the medieval era of Europe, advancements were being made: the rise of windmills, improvement in construction and architecture (particularly noticeable in Cathedrals), the creation of plate armour, and the development of the very first guns. Although the overall effect on the common man from generation from generation were not noticeable, gradual refinements in tools and methods gradually accumulated as the centuries went by, eventually making future refinements possible. Hell, they rediscovered the lost technology that was concrete eventually.
However, most fantasy writers ignore this fact and keep their lands at a developmental level equivalent to Europe in the middle of the medieval ages, around the year 1000, until the universe collapses. A knight's ancestors five thousand years ago fought against Orcs on the back of a great warhorse, wielding sword and lance, wearing plate and a greathelm, just as he does at present. At best, some groups in the universe may be more advanced than others (some peoples might be building castles and forging plate armor while others live as primitive cave men armed with flint axes and stone tipped spears), but nobody will be developing new technology. This also applies to social structures such as feudalism.
Even if an author claims that magic makes technological development unnecessary, it still often makes no sense as to why society decided to stop its progress so firmly in medieval times, as opposed to any other particular period of history, like the Roman empire or ancient Egypt (which was a remarkably conservative society, changing very little between 2000 BCE and 0 BCE and only adopting new technology when someone conquered them with it). If a writer gave any thought to it, they could give the argument that the middle ages ended because of the internal force of the renaissance as compared to Rome or Egypt which were done by external forces. Though few writers goe that far.
But hey, at least we get dudes with pauldrons.
Notable Examples of Medieval Stasis
Remember: Medieval Stasis is the norm of most fantasy worlds, so don't list everything under the sun or we will be here all day, only leave the most egregious or well known offenders
- Lord of the Rings: Tolkien was a naturalist that wasn't too fond of industrialization, (having lived though the First world war highly industrialized warfare) so the heroes of his stories preferred Medieval Stasis as well, baring a few anachronisms like clocks and matches. Of course, unlike most of the writers that he inspired, Tolkien had five hundred pages of background explaining why (namely because Middle-Earth was in a state of decline due to the ravages of Morgoth and Sauron, the gradual decline of the elves and the Dunedain after the downfall of Numenor and much of their technology was given to them by the Valar rather than inventing it themselves) so it's much more excusable.
- A Song of Ice and Fire: A really notable example, because not only has everything been fairly stable for thousand of years until the Great Fuckening of the current time frame, some individual families have had unbroken rule over their lands for a hundred odd of generations. That said should be noted that part of the backstory involves the bronze age First Men defeating the stone age children of the forest, who were themselves conquered by the Iron Age Andal invaders everywhere but in the Iron Islands and the North (who adapted and adopted the technology of their would be conquerers) and the records of the ancient days are spotty at best, full of mythical accounts and many of the Maesters believe that said events happened over a shorter timeframe.
- Forgotten Realms: Not only have things been more-or-less exactly the same for all of recorded history, there is a powerful, international, theoretically-good-or-at-least-neutral organization (the famous Harpers) actively devoted to making sure that no progress of any kind is ever made. Whenever anyone invents something useful (guns, locomotion, etc.) and tries to market it, the Harpers confiscate it. Whenever a good-aligned king tries to unite and stabilize the warring states, the Harpers murder his ass. Faerun hasn't budged an inch since Ao glued it together.
- Greyhawk: Though the fact that the current page on this oldest-of-the-old school settings is little more than impotent bitching at the moment, it also has a society where nothing much ever has happened or will happen to bring about changes in the lifestyles of its inhabitants.
- Dragonlance: Apocalyptic calamities come and go, but Krynn stays at pretty much the same level of pseudo-medieval tech forever, world without end, amen. And, no the tinker gnomes do not count, since their stuff almost never does anything useful, gets mass-produced, or catches on outside the gnomes themselves.
- Warcraft: In a cartoony match for the Dragonlance example above, Azeroth's many factions never adopt one another's technological advancements. Goblins and gnomes can invent as many steampunk robots as they want, none of their stuff will ever change the world in a concrete way. Even the aliens are mostly just sword-and-sorcery types.
- Ravenloft: This is probably the most interesting example. The Demi-Plane of Dread doesn't so much "advance" as it does "absorb some place where things are a little more complicated," and most of the Domains of Dread are already tailor-made just to torture their prisoners. Thus, though individual Domains might be advanced enough for common people to have firearms and gaslights or so primitive that they aren't even into the Stone Age (King Crocodile for the win!), they will almost never learn from or assimilate one another's technology. Each Domain will be mostly frozen into the level it's at, medieval or not. Amusingly, this works both ways: technologically advanced societies are no more likely to take up magic than lower-tech ones are to learn to use gunpowder.
- Warhammer Fantasy Battles: While the Empire, Dwarfs and to a lesser extent the Skaven all have technology some factions in Warhammer play this trope straight. Namely Bretonnia who are literally in Medieval Stasis despite one of the most technology advanced nations right next door, the Elves (all types) who, in their defense, may not have changed in thousands of years but what they have still works, the Warriors of chaos who are again literally medieval but in their case they're Medieval Vikings, Orcs who have not been introduced to the wonders of "Dakka" yet, the Lizardmen who although they make up for it by using dinosaurs still use wood and stone and lastly the Ogres who are pretty much in "stone age Stasis".
Notable Examples without Medieval Stasis
- Warhammer Fantasy Battles: The Empire and the Dwarfs are actually about the level of most European countries around 1500, at the start of the early modern period and the Renaissance. They're also advancing, albeit slowly, the problem is that they are under constant Chaos invasions, which don't help, and that the chaos gods are not above screwing with the world. Imagine what Nurgle would do to the guy who Discovered Penicillin in this world. The fact that the relation between the engineers and the cult of sigmar are not the best in the world does not help things at all. The other notable technology user are the Skaven, but the Skaven technology only effects there weapons (god help the world if they ever figure out sanitation considering what it did to our own population) further a case can be made that they don't use technology, but build machines that use magic given how much a role Warpstone plays in there technology. On the other hand: there is little practical difference between the two.
- Iron Kingdoms: The Iron Kingdoms setting is one of the best examples of steampunk. They're developed to the extent of the Victorian era (the mid-to-late 1800s), with a slow-but-growing industrial revolution and the discovery and development of electricity and chemistry.
- Eberron: Eberron is so-called "dungeon punk," so the technology is a strange mixture of all eras (plus a lot of magic!). It's one of the few settings that avoids both medieval stasis and outright steampunk, since magic is so common that it has effectively displaced technology in-setting.
- Ironclaw: The once-fantasy world is undergoing a pseudo-Renaissance shift away from magic and feudalism to machinery and Italian-style guild-republics. PCs are actually explicitly part of the burgeoning new middle class.
- Mystara: Depending on where you are, there might be airships, magic-powered technological conveniences, and drill-tanks to explore the hollow earth full of dinosaurs. Either way, things are a little less generic here in proto-Eberron.
- Pathfinder: The default Golarion setting includes relatively advanced technologies such as flintlock and matchlock firearms, the printing press, galleons (crewed by pirates reminiscent of the Golden Age of piracy in the Caribbean), and, in certain sourcebooks, steampunk/magi-tech spaceships. Not to mention the number of people whose clothes and equipment are explicitly based on 18th-century fashions (see, among others, Andoran, Taldor, and Alkenstar). Also, there's that one random corner of the world where aliens are trying to peacefully settle and/or invade, only to realize they picked the *one* corner of the world where pleas of "We come in peace!" are met with warcries and the judicious application of battleaxes to various vital areas. A recent sourcebook includes *lots* of super-high-tech stuff and different class archetypes that make use of it.
- Avatar: The Last Airbender: There is a bit of this previously (as well as implications of various major disasters), but in the modern times technology does move forward with the Industrialized Fire Nation with steam powered ships and land vehicles in A:TAS to the 1920s/30s technology of Legend of Korra with automobiles, radios and movers. Its somewhat implied as a result of an Enforce Segregation of the Nations by the Previous Avatars and other World leaders.
- Dragonmech: Dragonmech's setting used to be in Medieval Stasis, then chunks of the moon started to rain down on them along with Alien Moon Dragons riding the rocks down for a full-on invasion, people first hide underground but then a dwarf kick starts the creation of Pacific Rim sized steam power robots to fight the Dragons and the whole world is now in a full on steam power Industrial revolution without the gun powder.