A Shadow of All Night Falling (1979) by Glen Cook is a curious beast, a chimera inside a genre of chimeras. The book at times feels like an oral history, adventure, sword and sorcery, drama, and a few other things that I haven't quite identified. The plot seems simple enough, but wanders wildly from your presuppositions. At random points, the text devolves into confusion, while at others, the story stops delivering any energy at all. The points of view are myriad, far more than are fashionable now. All told, the book shows every symptom of being a first book, which this is.
Set inside his Dread Empire world, the story follows the tale of Varthlokkur, a wizard, a man named Mokker, a woman named Nepanthe, and Nepanthe's brothers, the Storm Kings. Their ambitions clash, where not everyone can be a winner, and not everyone can be a loser. Think of this story as the great-grandfather of Game of Thrones, where the rules of writing such a story aren't understood yet, but the power of such a story is recognized. In fact, this assertion isn't far from the truth. GoT didn't spring from Martin like Athena from Zeus's head.
This book represents the first steps of military fantasy separating itself from sword and sorcery. The common man using his wit and intelligence against godlike sorcerers begins its here. This is it. I've found no book further down the root of the military fantasy tree. As such, this book breaks so much new ground that that Glen had no hope of writing a decent book.
The character here seem decent enough and well differentiated, if a bit flat. You don't get anyone confused. They each have their own agendas and motivations, which is part of why this book fails on so many levels. This book was simply too complex for a new novelist to write. Consider Game of Thrones, where so many viewpoints requires a thick tome to follow. You could have easily doubled this book's length without it feeling padded.
If you are tired of turnkey fantasy, you should certainly consider this book. The stories and ides go in many interesting and unexpected directions. Likewise, a fan of older style sword and sorcery should feel fairly comfortable with the work.