I used to have a theory that the Ashlanders were based, perhaps not intentionally, on the Gaels. Mostly the politics and geography, and some aspects of their culture, seemed to be Gaelic. There are also many events in their history that seem similar to events here, although that depends on your interpretation of history.
However, I found out that the Gaels are only a part of the Ashlander's character, and that part may be a small one. They also include Assyrian, Mongol, Arabic, Phoenician, and Native American ideas, and it would be wrong to say that any one of them is more important than the other. If anything, the Orcish armour looks more Mongolian, and the Ashland camps could be based on anything from the Saami to the Ainu.
The Mongolians were horse warriors; the Ashlanders are not. The Mongolians are nomads, who follow the herds. The Ashlanders tell their herds where to go. The Mongolian economy is based on the raid, the Ashland economy is based on the export of expensive products. There are a few differences, but, as with the other nationalities, the Mongolian ideas are still there.
The fact that the Ashlanders have an ashkhan as leader; in the Ancient Mongol tribes, the leader were Khan
It's simply a Turkish title that was used by the leaders of tribes of Turkish origin, which then became the practice of many Islamic kingdoms, from the Phillipines to south Africa. It also doesn't have to be a tribal leader; it means 'ruler,' and could be anything from an emperor to the advisor of a chief of a small tribal branch that owns three farms near the border with Georgia.