Horselords (Forgotten Realms: The Empires Trilogy, Book 1) (Forgotten Realms: the Empires Trilogy, 1)

Between the kingdoms of the western realms and the eastern lands of Kara-Tur, lies a vast, unexplored domain. For centuries, the people of the realms have given little notice to the barbarians who live there. Then, one day, the wild horsemen unite into an army powerful enough to destroy the world.