This book is a first in the series or a trilogy and certainly has a lot of potential. It kept giving me the Queen of the Tearling vibes. There is a great evil in the world, the future seems bleak, the pages are filled with death and violence and all hopes rest on the prophecy of the sun queen who will defeat the evil forces. I did not like the first book in the Queen of the Tearling trilogy, and I think many people will not like Furtyborn either. It is too long, and definitely not a page-turner. But it lays the foundation of what's to come in the the rest of the series and creates the context for the world, belief system, mythology and history. I just hope that the sequels are really good, otherwise, the entire series is going to be a huge flop.
In short, if you like epic fantasy, queens, prophecies, magic, time travel - this book has all of these elements. It also has some steamy scenes that seemed a bit out of place to be honest, but nonetheless if you like romance in fantasy, this book has it as well. It just somehow fails to grip the reader. The characters are not well-fleshed out and I did not feel any attachment to them. I will definitely check out the sequel, but am a bit apprehensive at this point. 4 out of 5 stars (mostly for the complex world and potential).