Harry Turtledove 
Were Blood 

In the northern reaches of the Empire of Elabon, Gerin, called the Fox, battled to save his domain from destruction by the warlike Trokmoi and their wizard-leader, Balamung.Assisted by the giant Van of the Strong Arm, Gerin prepared to make the hazardous journey to the city of Elabon, there to enlist the aid of a sorcerer more powerful than the Tokmoi masge.Pursued by demons, beset by bloodthirsty nobles, and encumbered by the presence of the beautiful Elise whom Gerin had sworn to protect, the comrades encountered greater dangers than either had ever known.