Old Campaign:
Demons summoned by the eastern Emperor, were pathologically selfish and lazy. They summoned a race of horned therapods as middle management. Being mortal and horny, the spawned several generations that could not be unsummoned by then. Having a talent for bureaucracy and contract, they avoided becoming slaves, so the demons summoned in a race of small, strong idiots as slaves, that anyone could beat and boss around. Civilization grew, the people mostly prospered. However discontent grew and eventually someone took a swipe at the emperor. It was successful, so some of the demons returned to their planes. Others fought amongst each other until civilization was knocked back to subsistence levels. The idiot slave races rioted, until the middle management organized the people into a militia and chased the little creatures into the Western mountains. Eventually the remaining demons were unsummoned, cancelling out a lot of the magics, leaving a desertified land with scattered small towns and ruined cities near the broad rivers. In the West, lots of little polities, coalescing into nation states with few demihumans if any, except a forest of elves that everyone avoids as they are of the fey, and not to be trusted.
New Campaign:
Currently run as pBP, No-to-Low Magic campaign taking place in a late classical period. The players are artist colleagues with furry tendencies (all women), so the Demi humans are”furries”, specifically Lupines, at the edges of the human empires (Byzantium Analogue, and. Persia Analogue to the east, fractured by some internal rebellion s. ). The are having fun with it and tend to be more bloody minded than expected.
No Tolkien races in sight.