Kindly note: This series is very much meant to be read in order. If you haven't yet read the previous books of this series, this review may contain spoilers about how they turn out.
Now that it's clear that Matt/Sköll, along with the other three Alphas of All, have risen to meet the threat from Völsung, the young man wants to learn more about the history of the Vargr, Cubi, and Sleipnir and how they came to be allies along with the humans. The Cubi king Nol-Elakdon, Matt's Vargr grandmother Thyra, and the Alpha stallion of the Sleipnir all agree to tell the story of the events that came after the last Great Pack War more than a thousand years ago.
The arc of this series is very roughly paralleling that of The Cubi series that came before it. That series also had an installment similar to this one. A sort of break in the narrative to fill in some of the backstory of how the current state of affairs came about. As in the History of Beauty story of The Cubi series, it's very much a tale about how the coming of Christianity to the north countries changed the relationships between the humans and the children of Loki, who effectively had to go into hiding, although for the Vargr, they could essentially do it in plain sight.
The “history lesson” takes up a little more than half of the book. The remainder returns the focus to Matt as he digests what he has learned and faces a new challenge from the Völsung. One of the overall themes of the series, which comes through strong in this story, is the need for Matt to find a balance between the three sides of his nature. The human, Vargr, and Völsung inside him each bring their own strengths but also have needs.
It seems that Matt's human side is the one with some of the hardest issues to address. He still struggles to be the kind of boyfriend he thinks Rasmus wants, and the underlying trauma that's stopping him finally comes to light in a funny but sad conversation with his old high school friend, the Cubi king Daniel.
“Historic Ember” is available from Amazon.