Goatfolk settlements tend to lie in out-of-the-way places. The largest concentrations of ibixians can be found in the grassy steppes and foothills surrounding the Blackcap Mountains in northern Breland and southern Aundair. During the Last War, Aundair used conscripted goatfolk infantry units against armies from Breland and Thrane. After witnessing firsthand the effectiveness of the ibixian troops, Breland followed suit. In a battle known as the Clash of Horns, goatfolk from Aundair faced goatfolk from Breland on the field of battle. After a brief yet bloody skirmish, the ibixians on both sides joined forces and turned against the armies of Aundair and Breland. Both armies were routed, after which the surviving goatfolk retreated to the Blackcaps. They remain in hiding to this day, fearing reprisal for their treachery.
Source: Monster Manul III