From publisher blurb:
Most kingdoms on Hârn rely on an elite mounted warrior class for protection and maintaining the rule of law. As a result the horse is by far the most popular form of transportation on the island for nobility, and its use in warfare is almost universally considered the pinnacle of martial achievement.
There are two indigenous breeds of horse on the island of Hârn. Both have a common ancestry which existed on the island during the Age of Sindarin, and perhaps earlier. Four major breeds exist on the continent of Lythia, each originating in the four great horse trading nations of Quarphor, Ketarh, Reksyna, and Hacherdad.
Most horses found on the island of Hârn are a mix of the four major Lythian breeds. There are, however, distinctive regional variations brought about by generations of ostlers responding to local events, economics, and the availability and exchange of breeding stock.