Magic Versus Science: it is said in the second game that humans and elves are not indigenous of the world they live in but that during a convergence of spheres event humans arrived on metal ships and elves arrived on white ships (some non supernatural monsters apparently arrived in similar fashion hence why they have no real place in the ecosystem) hinting at the fact that, while magic exists in this universe, there are some remnants of a higher tech left behind. Coincidentally, Witchers are mutants, genetically mutated humans to be precise (notice the double Helix symbol in the mutagens menu and the distinctly cellular look of the mutagens themselves which some fans disliked for their sciencey look) created to deal with things normal humans could not (the supernatural) and a lot of well read individuals in the game know an awful lot about mutations and evolution. Sounds like the Witchers might be the earliest attempt of the newly arrived humans to fight back the hostile, unknowable forces of this universe using their own technology.
Based on the novels it seems more likely that magic is science. The sorcerers study physics and genetics in order to gain the understanding they need for their spells to work and supernatural forces like Destiny are treated with the same seriousness as, say, gravity.
By the third game seems like even the "monster" are what we call "aliens". They came from other worlds, just by portals instead of UFOs.
Witcher's world nations real life counterparts.
Well, Redania is obviously Poland, Nilfhgaard is Germany/Ottoman Empire, Bouclaire is France, Velen is Netherlands(?)(because is infested by swamps like Medievial Netherlands), Kaedven is Russia, Ofiar is Middle East. If you tropers got another ideas help me.
Actually, Temeria is much more like France in terms of iconography and heraldry, political power and military/ civic structure while Toussaint duchy is an epithome of a medieval French vibe, with good wines & food and strong chivalric mounted knights. With added pinch of Italian landscapes and rural architecture. Judging from its heraldry, Cintra is England.
Cintra in many ways resemble Eastern Roman Empire (Byzantine) or The Kingdom of Hungary. Originally a rich kingdom with a number of vassals, but quickly defeated in a war by the Empire and absorbed.
The kingdom of Kovir and Povis could be alternatively seen as a representative of pre-WW 1 USA. The backstory says that it first started as two colonies of Redania where some of the younger brothers of aristocrats were sent, it continued expanding and annexing neighbourhood petty kingdoms, then gradually expanding its industrial outputs due to abundance of mineral resources and strong imigration of dissatisfied poor craftsmen from other countries. In the decades before the main storyline, it emerges as a strong kingdom with a powerful navy that ostentatiously stay neutral but plays with both sides.