This is where the series starts to come into its own: It provides the backstory of the protagonist, Nizar, back during the founding of Hogwarts around 980. It’s extremely well-researched regarding the realities of the British Isles back then, including the multitude of languages and kingdoms, their squabbling relations, the international nature of Europe, and much more. (To be clear: this is my version of a glowing review. I live for this shit.)
I nearly made it a five-star book when I realised that it even intentionally makes the spring equinox take place on March 15th due to calendar drift, which makes me be fucking in love.