The Witcher is a series of novels written by Polish author Andrzej Sapkowski, but is better known for the series of video games produced by CD Projekt Red (much to his chagrin; he regularly rotates between dismissal of the medium, lamenting the deal he made with them, and entering into litigation). They focus on the life and times of Geralt of Rivia, one of the titular Witchers (alchemically-augmented superhumans tasked to be monster hunters) in a rather dark fantasy setting where fantastical monsters are becoming resurgent and humans are little better than the monsters.
An important part of the discussion of history in The Witcher universe is that the setting exists in a multiverse; every so often there is a "Conjunction", when universes meet and species cross over between them, and if taken literally then sometimes new universes are born and old ones are destroyed during these (although this could be a fancy way of saying that the species immigrating back and forth cause major changes).
Due to Sapkowski's general disinterest in worldbuilding beyond what is necessary, what's known about the world is mostly just what pertains directly to the stories themselves. Continents, cosmology, far-off cultures, and large chunks of history are just blanks, to the point that the author himself refers to fan-created maps in later works.
The area that almost all stories take place in is simply known as "The Continent" (there is also "The Western Continent" in a few stories), and was native originally only to Gnomes and Dwarves. Elves, called Aen Seidhe, arrived from parts unknown in boats thousands of years ago and established kingdoms while having sporadic wars with Dwarves. After the first Conjunction humans arrived from another world that had been rendered lifeless by calamity, as well as a second group of Elves called Aen Elle. Humans spread out rapidly, initially living in peace with the Elves and learning both magic and civilization from them. However the human territories aggressively pushed borders as the human breeding outpaced that of the Elves, resulting in more and more wars, massacres, and forced removal of Elves from their own cities. Eventually the Elven youth began to fight back, initially destroying their own cities in order to prevent humans from easily settling into new regions. The Elves were unable to take on the sheer human numbers, and the youth of an entire generation were killed. The Elven royalty reached out to humans who had benefited from their shared past (so wizards) and tried to establish relations, but the ignorant human masses killed an Elf Princess and her human husband which resulted in another Elf/human war. The Elves lost again, losing one of their few remaining kingdoms and souring most Elves on humanity forever.
When the Second Northern War began the Elves established an army of guerilla Scoia'tael freedom fighters, made up of the various non-human races that mankind had marginalized. They managed to win back one of their kingdoms, although their best soldiers were given to the humans for war crimes and were summarily executed.
During the Second Conjunction, all (or almost all depending on interpretation) Elves left the world, because literally anything is better than remaining with humans. Witchers came back into prominence due to the new influx of monsters.
- Geralt of Rivia - Our main protagonist and one of the last Witchers, a race of alchemically augmented mage-warriors. He's a fairly no-nonsense guy though he's very much struggling to keep the inhumanly impassive perspective in check.
- Ciri - Geralt's sorta-adopted daughter, proclaimed his Destiny because of a tradition called the "Rule of Surprise" (A tradition in which one person does a service for another, and the recipient must repay this favor through a means that satisfies intentionally-vague criteria). After her mother and grandmother died in a siege waged by barbarians, she manages to wander into Geralt's life, and so he decides to raise her...as a mini-him. This is quickly stopped and she's sent to a proper school to learn. It's pretty clear that she's far more important than she seems as her unnatural height and uncontrolled bouts of magical power indicate that she might have some inhuman blood insider her. According to the games, she’s also been to the world of Cyberpunk while trying to escape pursuers (made possible by the act that CD Projekt RED works on both franchises).
- Dandelion - Traveling bard and one of Geralt's few genuine friends. He's something of a complete idiot and a coward, but he's also the friendliest folks around and is always looking for material for his ballads. He's something of a nuisance, but he's also one of the most well-traveled people around.
- Yennefer of Vengerberg - The closest thing Geralt has to a formal relationship and the closest thing that Ciri has to a mother, though she's totally a bitch at times. She's a sorceress who's manipulative but also very much despises her condition of infertility (a result of becoming a sorcerer) and this is one of the great points of contention between the two of them.
- Triss Merigold - Sorceress with a teenage-like romantic obsession for Geralt that he doesn't share. She doesn't have too much presence as a character in the books, then she jumps to being a main character in the videogames when she takes advantage of Geralt's amnesia and Yennefer's absence to fulfill her fantasy of being the witcher's main lover. She may remain as such even when he recovers his memory. Aside from that dick move, she is very kind and light-hearted, and remarkably, she is one of the few sorceresses that doesn't continuously behave like a bitch.
- Emhyr var Emhreis- the Emperor of Nilfgaard, which is essentially a superpower based mostly off of Rome, though their aesthetic is more medieval German (as far as "evil empires" go, though, it's rather morally grey). He is known for being a cold, ruthless and pragmatic son of a bitch who will stop at nothing until the continent knows only the glory of Nilfgaard and all other kingdoms and states are subjected underneath the Golden Sun. Ciri is his biological daughter, and he desires her to continue his line, as he's head of a prophecy that states that her bloodline will eventually control the world. Has a series of long-winded titles, including a ridiculous "The White Flame who dances on the graves of his foes."
- Eredin- the elvish King of the Wild Hunt (a group of supertall and buff elves in scary black armor), and widely considered to be THE main antagonist of the games. He lead a genocide of the human population of his home planet, poisoned his old king with a spiked aphrodisiac, and when a mystical force is known as the White Frost (either an encroaching Ice Age or the heat death of the universe) began to threaten his world, he started to hunt Ciri in order to use her to invade her world.
- Vesemir- Geralt's mentor and the closest thing he has to a father. He is a witcher with roughly four centuries of experience under his belt and was the sole survivor of an assault on the Witcher stronghold at Kaer Morhen. (Geralt and the few other witchers were away on contracts when this happened)
- Radovid- At first Prince and then King of Redania, the Poland-Lithuania-style country. Stylized as Radovid V the Stern, he starts off as alright-ish and eventually becomes a real fucking prick by the point of the third game, ordering the extermination of all magic-users due to Philipa and her Lodge of Sorceresses backstabbing him and murdering his father, as well as ordering the suppression of non-humans. Despite his ruthlessness and "madness", he is also shown to be a very clever tactician and strategist.
- Sigismund Dijkstra- Think Winston Churchill if he was a medieval Polish intelligence official. Gruff, fairly obese, and intensely patriotic to Redania, he believes in using methods other than war to achieve the state's aim, but he won't hesitate to bash in a motherfucker's skull if it means Redania remains safe. Had to flee his country when Philipa sent assassins after him and ended up becoming the head of a gang in the free city of Novigrad, while still secretly retaining his loyalty to his homeland.
- Philipa Eilhart- the "Jewel of Tretegor", and probably the biggest reason why sorceresses and mages are seen in a negative light in the Northern Kingdoms. She is the head of the Lodge, the magical advisor to Redania's king, and a complete and utter cunt. Even Yennefer hates what a stone-cold bitch she is, noting that she is manipulative, power-hungry, cold, and ambitious. Radovid eventually tires of her bullshit and ends up exiling her, but not before putting out her eyes.
- Crach an Craite- the Jarl of Ard Skellig, which is part of the Skellige Isles (essentially comprised of a people who are more or less Gaelic-Norse in culture). He is a steady ally of Geralt's, and noted for being an exceptionally brave and fearsome warrior, even giving witchers pause when facing him. He is a just and fair ruler to the people on his island, and a terrifying opponent to face in a raid, to the point where Nilfgaardian and Northern naval vessels steer far away from the isle, lest they suffer the wrath of the "Wild Sea Boar".
While there are six novels, they were not released in order of continuity. The first and fourth novels (The Last Wish and Sword of Destiny) are just a bunch of short stories using the same cast and settings while the rest of them are all focused on a particular central plot.
- The Last Wish: The introduction to the world of the Witcher, explaining who Geralt is, the world he lives in, and his work. As a collection of stories, there's not much of a greater overarching plot, the closest being his decision regarding hiding out in a place where he's clearly being hunted.
- Blood of the Elves: Introduces (Numerically) Ciri and how Geralt decided to raise her in Caer Morhen. This is eventually halted after Nenneke reminds him about how raising a child isn't the same as training a Witcher and sends Ciri over to a school that actually teaches magic. It is here that Ciri also receives some instruction from Yennefer.
- A Time of Contempt:
- Sword of Destiny: Despite being released internationally as Book 4, this was actually written and set after The Last Wish. This does mean that it's another set of short stories, though the overarching plot is much more obvious. This is also the chronological first time we are introduced to Ciri.
- Baptism of Fire:
- The Tower of the Swallow:
- The Lady of the Lake:
- The Season of Storms:
- The Wild Hunt:
CD Projekt Red is responsible for releasing the three main Witcher games (with DLC) alongside Gwent, a digital card game and competitor to Blizzard's Hearthstone, and Thronebreaker.
There is actually an RPG that lets you play around in this setting made by R. Talsorian in 2018. It generally lets you use the basic engine of d10+Stat for getting things done. You get a small list of classes and only three races (Human, Dwarf, Elf) with the actual Witchers being a race-as-class affair. There's a lot of background rolling, some truly nasty ways for crits to work you over, and a rather vast crafting system.
It's not horribly designed, as such systems go, and all of the classes and subclasses feel unique and distinct, but the skill system is schizophrenic as hell, not sure whether it wants to collapse similar skills together into super-skills or split them out into granular sub-skills, the random backstory generator tends towards grimderp and cannot be removed or replaced with something that lets a player pick, since some results offer gameplay benefits and penalties, and the crafting system is, at once, the worst kind of busywork math homework/bean-counting actuarial nonsense and absolutely necessary since everything in the game is designed to be more expensive than necessary to force you to engage with it at gunpoint.
Combat's also not bad, and has a unique stamina mechanic where players essentially have a finite-but-replenishing currency they spend by taking all kinds of actions, but it's very random and lethal, so having a medic is also something the party needs at gunpoint.
Finally, although they are the supposed draw of the game, Witchers are generally restricted to one per party, and while they are very good at hunting and killing monsters, they are very bad at everything else, they suffer extreme social penalties, and while Geralt, by virtue of being a protagonist and a high-level character, is good at all kinds of things, most Witchers really, really need to specialize. Honestly, the average man-at-arms is just as good at fighting as the average Witcher, again, outside of monster stuff, and better at doing other things that don't involve monsters or tracking.