Alright, time to write some s**t up like I promised.
Hopefully this will give players an idea of what to do, so we don't have any mix ups.
The first thing I would like to say, is that the country has been at war for a very long time. In fact, there was a war very recently during the older lord's life time. To give an estimate, Lord Eyre's brother was killed when he was in his twenties. This explains the reason for the shifters being born in the older siblings, rather than the young. Also why the shifters are in the same generation.
This of course ties in with trade.
Yes, the regions definitely trade with each other to keep things easy and efficient, but there isn't a lot of trust between them. Most of the lands have learned to be self sufficient because of the war... To a point.
The Halles provide food to the Yates, the Elynbrigge, and the Beausons. I am hesitant to say more, because it's not realistic. They don't have a lot of land as it is and the Eyre are fully capable of providing for themselves. Yes, the Eyre have forests, but they also have farm land.
Now to give an estimate on what each land has:
The Yates: Navy/fishing, Population, Wealth, fruit production. Also loyalty from the Halles. Most support from other lands, and the title of "king" to aid them. This is a valuable asset because of the nature of the war.
The Beausons: Best Navy, trade with foreign countries, and the Most wealthy. Potentially the best spy-network/the best scouts.
The Elynbrigge: Very experienced in combat from the constant battles with trolls. They have a Calvary, trained pikemen, and a fortress made from the rocks of trolls. (Troll rock has special qualities. They also have iron ore and crystals.) Standing army, in the sense that their population has a larger amount of combat experience than the others.
The Halles: High food production, Standing army (though it's not too big), Navy, and what will be the knowledge to make steel. (if not the best steel in history, but this will be limited to a few weapons.)
The Eyre: Lumber, iron ore in some regions, farmland, furs/leather, bountiful meat supply. People good at archery, hunting and herding. Also likely have posts or patrols along the elynbrigge border already, due to the issues between the families.
The Lathams: All the iron ore you could ever want, plus a lot of other different metals. High defense since they're in the mountains, Navy, Fishing, and oil from whale hunting.