The premise is similar to A Song of Ice and Fire. A hundred kings are fighting to decide who will sit on a certain special throne, and they have to figure out and unite the empire before a certain undead threat arrives and destroys the world. The protagonist, Jorg Ancrath, is a child who watched his mother and little brother be killed as a result of that dispute between kings, and after learning that his father will do nothing about it, he runs away and joins a band of thieves. Over the years, he becomes their leader, and eventually comes back to get his revenge and make his own moves at the empire game. He is far from being a hero and he knows it, but he is extremely resourceful and pragamatic, tends to find the most unique solutions to problems (usually some bloody variation of cutting the gordian knot), so he may be just what the empire needs to stop the incoming undead threat.
It's very good. Particularly the last 2 books. First one is mostly good too, but it is a little harder to get into because the protagonist is a complete sociopath (in the first 50 pages, he kills multiple innocent people and rapes someone, so that can be an entry barrier for some people). But if you can get through knowing you don't have to root for the guy, plot stuff will eventually happen and he will start developing, so he will become more of an anti-hero as the story goes, which is represented by how the cover of each book has a lighter color than the previous one (but never fully white). The story tests the absolute limits on whether it's possible to redeem someone, and the way it ultimately resolves it is... unique, to say at least.
It also uses anachronic storytelling order, which is something I love. Each book has 2 or 3 narrative lines that are usually happening at different points of the timeline, and the stuff happening in the present makes more sense as you learn what happened a few years ago. There is one trip that takes the entirety of Book 2 and 3, while the other half of each book is influenced in the future by the things that happened during that trip. Each book has at least one huge plot twist that explodes near the end of the book as you learn what happened in the past, and changes your whole perspective.
Bottomline is, not a series for people who are sensitive to gore/violence/rape (though the last one doesn't tend to be graphic) or require their narrator to have at least some semblance of humanity (at least in the first book), but after reading, I have to admit it is a very good series. It also fulfills that craving some of you may have for an actual, quality ending to a story similar to ASoIaF which doesn't extend endlessly or split in too many characters (Jorg is usually good at ensuring superfluous chartacters don't stay around, for that matter).