Does he succeed or will the Forgotten Realms have another war in the Spine of the World?
Yes, he does. How do I know? Because I read the damm prologue!
Salvatore gave away the ending at the very start of the book. The prologue is set 100 years in the future with Drizzt Do'Urden still around. Now that's okay as I never expected them to kill off the drow, but the prologue then began revealing that the orc King Obould succeeds in the creation of The Kingdom of Many-Arrows for the orcs and that Drizzt supports this kingdom. Not only that, he was the one that convinced Breunor of the need for peace. Great! Super! I can stop reading the book right there, can't I?
I have to say this is the only book I have ever read that I hated from the very start! Salvatore did not just gave away the ending at the start; he even tell you how the end came about! By the way, if you are reading The Lady Pentinent series by Lisa Smedman, skip the prologue as it gave that one away as well. What in the world was he thinking!
Regular characters like Drizzt, Cattie-brie, Bruenor, Wulfgar, and Regis all make appearances in this novel but this is not actually a Drizzt novel. He is in the thick of things but this book give more info about Obould than anyone else. Outside the barbarian Wulfgar (who left for Icewind Dale) and Drizzt's wife, Catti-brie (who is on her road to being a wizard), nothing really happen to the mainstays of the series. The plot of this book is about Obould, the creation of his kingdom, and the revolt he faced down from the half-orc/half-ogre chief, Grguch.
Overall, the book was pretty solid. If you like Salvatore's other works, you will like this one. Just remember to skip the stupid prologue.