The elevator pitch I'd give for this book is Game of Thrones meets medieval Japan written with a concise writing style more reminiscent of Ursula K. Le Guin than the long winded authors of most modern fantasy.

The author admits to taking inspiration from classic Japanese tales like Tale of the Heike, and the writing style comes across as a far more readable homage to those classic works.

Characters are believably flawed. Those who are "bad" often have legitimate gripes, while those who are "good" commit questionable actions. Most are tempted by greed and ambition regardless of which side they are on.

I'm really looking forward to the rest of this series, and will have to check out the author's earlier works.