The Westerling tribe of the Caturiges (battle-kings) regained their independence after the fall of the Ardean empire. Although their royal family was wiped out by Dengwur, they chose a new one under the direction of the Druids of Choir Morag. These druids also helped them to regain their independence from Dengwur during his war with the Old Ones. By religious tradition, each district of the tribe will have 10 hamlets and 1 chief's Rath (fortress) Each district can be considered a market class VI for trade. The only larger settlement is Seatun and the nearby Prince's fortress, which together count as a Market Class V settlement. The land is mostly self-sufficient and does not engage in much trade or large scale production.
Each district will have 800-900 families and will be ruled by a chief who will be 4th to 7th level. There are 15 districts in the Principality, two of which are the Princely Districts, ruled directly by Prince Gerdun (Fighter, level 9) himself (the one around Seatun and the one immediately to the south). Choir Morag is a druidic sanctuary on a holy island in the sea to the North. The High Druid Council meets here and helps guide and protect the principality.
So, basically fifteen domains, of 800-900 families each. Of course there will be politics. Each district will want favors and concessions for providing troops. Others might just provide completed units for pay.