As you'd expect in a Viking saga, there are plenty of moments of violence in this book, but - unlike many Viking books for kids - the violence feels integral to the plot and an understanding of the period in which it's set, rather than gratuitous.

There are lots of allusions to Ylva's Viking beliefs in the gods, in their power to control her life, and to the Viking folklore that describes men who turn into wolves. Cathryn, Ylva's no-nonsense guardian, clearly has beliefs of her own, but she emphatically does not believe in magic or in the Viking gods' demand that revenge be taken for a life snuffed out, or their supposed ability to manipulate Ylva's destiny.

Ylva's mother is murdered at the very beginning of the book, and the subsequent story deals with her grief and her trauma to a large extent - which is so sensitively and honestly and beautifully handled by the author.

It's clear that Ylva struggles, whether through trauma or neurodiversity, to express emotions - she imagines that her dog, Geri, is still with her and talks to her, she struggles with physical contact, and will not admit to being afraid - all of these quirks are met with kindness and understanding by Cathryn, the Saxon woman who has Ylva under her protection.