While The Witcher schools are very prominent in CD Projekt Red's videogame series, they are not really ever referenced in the books. It turns out there is a reason for that – the Witcher schools don't actually exist in the original source material.
In a recent Q&A on Reddit, Andrzej Sapkowski, the author and creator of The Witcher novels, discussed his feelings on ‘Witcher schools', explaining that CD Projekt Red got the idea from a single sentence found within The Last Wish:
“The issue of ‘Witcher schools’ requires – I apologise – a longer explanation. A single sentence about some ‘School of the Wolf’ mysteriously made its way into The Last Wish. I later deemed it unworthy of development and narratively incorrect, even detrimental to the plot. Therefore, later I never included or referenced any Witcher Gryffindors or Slytherins again. Never.”
“However, that one sentence was enough. Adaptors, particularly video game people, have clung to the idea with remarkable tenacity and have wonderfully multiplied these ‘Witcher schools’. Completely unnecessary”.
For those who don't know, The Last Wish is the very first Witcher book, collecting a series of short stories from Geralt's time before the main novels. While Sapkowski had abandoned the idea of ‘Witcher schools', the idea did catch on amongst video game fans, and it is expected that CD Projekt Red's next game, The Witcher 4, will explore this idea further with Ciri setting up her own camp of Witchers.
Sapkowski would like to set the record straight in future books and may “shed some light on the issue of Witcher medallions, their significance and their connection to specific individuals”. On top of that, future editions of The Last Wish may be edited to remove the sentence about the “School of the Wolf” entirely in order to correct the lore.
KitGuru Says: As someone who got into The Witcher via the games, I've always liked the idea of different Witcher factions. However, it did always stand out as something ‘game specific' when going back to read the books. Now, we know why that is.