Otfried Preußler's 1971 young adult novel Krabat (which in the English translation by Anthea Bell is called The Satanic Mill, and yes, I do think that the book title for the English language edition for one does tend to give away a pretty major and problematic spoiler and for two also would sadly and likely immediately put The Satanic Mill on the hit list of puritanical, of religiously fanatical mentally deranged book banners simply due to the inclusion of the word satanic in the heading) takes place in 17th century Germany (or rather in what is now Germany, as in the 17th century there was of course no Germany yet but rather a number of independent principalities and kingdoms) during the Thirty Years War. And considering how much general hardship, starvation and horror were both the direct and the indirect result of the Thirty Years War, the back story of Krabat, of the main protagonist being a fourteen year old Wendish teenager alone, desperately poor and needing to find a profitable manner of employment to make ends meet certainly makes very much historical sense, with the poverty stricken orphan of the book title shown by Preußler as thus almost immediately hugely enticed by those dreams he keeps having, by a rough voice telling Krabat to make his way to a mysterious water mill to work as an apprentice, but which actually and massively creepily turns out to be not a traditional mill at all but instead a school entirely committed to black magic. So yes, I guess Anthea Bell calling her translation The Satanic Mill is kind of correct in and of itself, although personally, I really do wish Bell would just leave the title as it is, as Krabat, since I certainly find it considerably more textually interesting slowly and not right away realising that the mill where Krabat will be working is something horrifying and infernal, that the Devil himself is at play and must be overcome (and that this is also and therefore a matter of life and death for Krabat himself).
And indeed, in the three years of his traineeship at the mill, Krabat (and the other eleven apprentices), they are meticulously and with much textual detail shown as being instructed by their teacher, by their master (described by Otfried Preußler as white faced, wearing a black eye-patch and using a book of necromancy that is chained to a table) how to turn themselves into ravens, how to make wells run dry, how to read minds. But while at first, Krabat (who figures that necromancy could be a profitable trade, and that above all, he desires and also needs to learn something that will make money) willingly changes into a raven for his Friday evening lessons and also becomes pretty much a star pupil, he gradually realises that no one is really ever free to actually leave the mill except as one of the yearly fatalities which pay the the master's debt to Lucifer, that what the mill is grinding up in Krabat are in fact human beings, are the corpses of the apprentices selected to be sacrificed to Satan, and while yes, the key to Krabat's successful escape, to his salvation (namely the love of a pure woman) may be rather disappointingly simple (and also rather a bit like a deus ex machina on Otfried Preussler's part) and in particular when compared to Krabat's foreboding dreams of his likely demise and the wit of the lessons he learns during his time of indentureship at the mill, well, the ending for Krabat is still nicely and folklorically satisfying (although that the woman to save Krabat's life must be pure, must be virginal, this does make me personally a bit annoyed, although I doubt that I would have noticed and been all that frustrated by this had I encountered and read Krabat as a younger reader).
Now with Krabat, Otfried Preußler's descriptions of the mysterious rituals and events of the occult are richly nuanced and impressively detailed (as is his knowledge of the machinery of a water mill for that matter). However, the combination of realism and fantasy in Krabat kind of often seem to exist as two rather separate entities, and for me, in a school of magic where things are accomplished with the power of incantations and pupils can turn into ravens at any moment, Preußler's countless details about the mechanism of a real mill and the drab life of the trainees do tend to become increasingly tedious, not always all that smoothly incorporated into the fantasy elements and vice versa, and not to mention that the reader of Krabat also never really learns why the evil master keeps up this school and why he has chosen Krabat or the other boys for his disciples in the first place. And since in the supernatural as in the natural world, some motivation is of course necessary, this lack of external and internal drive, while this does not make Krabat unreadable for me and therefore still a sufficiently interesting story, still a decently readable account, it ultimately also shows Krabat as being a tale that kind of feels as though there are two entirely disconnected narrative threads present and which never really do seem to mesh into one and as such leave me personally feeling a bit textually frustrated (because yes indeed, the realistic parts of Otfried Preußler's text for Krabat and the fantasy elements are really not mingling all that well for me, and to make Krabat into a truly memorable fantasy or fairy tale like story, this would definitely need to occur more thoroughly).