As we know there are about 18,000 Pure Horse People in Dragon Pass. They all belong to one tribal group – with Yelm Sun Lords as the tribal leaders, aided by Yelm Elders and Golden Bow shamans. The total number of these Yelm Rune Masters is probably somewhere around 100 – for convenience, let’s say 60 Sun Lords, 25 Elders, and 15 shamans (there are about 5000 Yelm cultists. 2% of that is 100). The tribal king is the leader of the tribal Yelm cult.
We’ve got a whole bunch of extended kinship groups here, led by Elders. All of the Pure Horse people consider themselves noble, but there are of course kinship groups that are more or less powerful than the others. I suspect we have a number of traditional bands or clans, most of which date back to their acceptance by Ironhoof (so say around 1250). So let’s say there are 9 clans, each with two elders, and then 7 tribal elders that serve the tribal king. That gets us to 25 Elders. Some clans have more Sun Lords than others, and we have the Golden Bow as a cross-kin or tribal magical society.
Now the women worship Ernalda and Hippoi and care for the horse herds. They marry into the patrilineal and patrilocal clans, perhaps bringing horses as a dowry. They raise children, care for the horses, prepare food, manage the households, etc. But as Ernalda cultists, the women also have the ear of the great Feathered Horse Queen, before who even the Elders must prostrate themselves. The Feathered Horse Queen is the indisputable ruler of the Grazelands. She is backed by the Humakt cult, the Lightbringer cults, her sisters at the Shakers Temple, and by the gods and spirits of Dragon Pass.
So our clans might have around 2000 people on average, with some having more, and some having fewer. However these clans – or divisions (which is probably a better word) – are stable and Yelmic, with much greater stability than Orlanthi clans (but also far more ceremonial and far less dynamic).
Now among the vendref farmer communities we have some 14-20 clans and village chieftains, and these follow the Orlanthi norms. They also accept the Feathered Horse Queen as their ruler, but are not part of the Pure Horse People tribe.
It is worth remembering that most of the Humakti come from the vendref communities.
As an aside, remember that the vendref worship Orlanth and Barntar, as well as Ernalda, and those cults number almost as many worshipers as Yelm. The towns are tied to Sartar and Tarsh, and there are over a 1000 Humakti among them. In short, the PHP and the vendref co-exist in a balance that is maintained by the presence of the Feathered Horse Queen.
There are about 5000 Yelm cultists. 2% of that is 100.