Wolf's Call - Anthony Ryan

Vaelin Al Sorna is a living legend. It was his leadership that overthrew empires and his sacrifice that saved the Unified Realm from destruction. Now he lives a quiet life, his days of warfare behind him.

Yet whispers have spread across the sea of an army called the Steel Horde, led by a man who thinks himself a god. When Vaelin learns that Sherin, the woman he lost long ago, has fallen into the Horde's grasp, he resolves to confront this powerful new threat.

To this end, he travels to the realms of the Merchant Kings - a strange land ruled by honour and intrigue. And as the drums of war echo across kingdoms riven by conflict, Vaelin learns that there are some battles even he cannot hope to win.