And now, a brief overview of the Cambrian Confederation:
Each of the thirteen kingdoms are very much independent. Think of it more of a Staatenbund than a Bundesstaat, if such concepts existed back then. The kings each rule over their lands with very high autonomy. Once a year, the Cambric Council meets in the holy grounds of Cairnnewydd to discuss matters such as foreign policy and the common army and navy, but they have little power elsewhere. Instead, in order to understand Cambria, one must understand its constituent kingdoms.
Ceredigion Militarily, they are the most powerful kingdom in the Confederacy, mainly because they havent lost nearly as many men to the Rygi. In addition, they have access to much of the coastline, and while Cairnnewydd technically isnt a part of their territory, it is certainly well within their borders. They tend to by rather aggressive due to the fact that its not going to be their guys who will be dying.
Powys They are a major rival of Ceredigion, mainly due to the fact that most trade has to go through the much more urbanized ports of its neighbor, who tends to levy a hefty duty. In addition, they are somewhat displeased with the current political situation, due to the fact that the more influential Ceredigion tends to get its way.
Gwent A small kingdom, they are usually dwarfed by its neighbors Ceredigion, Powys, and Dobunni. They tend to side with the Ceredigions in disputes, typically in return for lower levies on goods.
Dobunni Their most notable claim to fame is the major port along the Afon Hafren[1], which provides most of their wealth. They provide the trading center for several inland kingdoms, though they tend to find themselves competing with Ceredigion, who tends to be more accessible to foreign and northern trading partners. The border with the Rygi tends to make them rather paranoid, and they usually try to push for a stronger navy.
Dyfnaint Typically, they are one of the most ardent supporters against the Rygi, being almost cut off from the rest of the Confederacy and whatnot. They tend to be rather worrisome of Rygi power and are the source of many border skirmishes over the past fifty years. They also would like to see a strong navy, for obvious reasons.
Ancalite Originally from the central stretches of Afon Tafwys[2], they have been forced upriver after the arrival of the Germans. They are always on the front lines, and they tend to be the frequent target of raids. They are mostly in favor of raiding the Rygi (since theyll end up getting the money!), but they dont want to have to deal with the bloodshed of all-out war.
Pengwern Once a part of Powys, Pengwern became a kingdom in its own right around the time of the first Germanic invasion. Still, they tend to look up to and be somewhat dependent on Powys for support, and thus almost always sides with their benefactors to the west.
Catuvellauni Like the Ancalites, they too were forced from their native lands along the Thames. Unlike the Ancalites, however, they have a strong desire to return to their home and drive the Germans to the sea.
Cornovii A small kingdom located along Afon Merswy[3], they are typically dwarfed by their neighbors when it comes to policy. They are one of the few kingdoms who outright support peace, though that can mostly be attributed to not being on the front lines and having nothing to gain by winning.
Elmet They are a fairly weak kingdom despite their size. Theyd rather not fight if they dont have to, due to their proximity to the Rygi. On the other hand, they are in favor of enlarging the common army, so they would have a better time defending in case things go sour.
Rheged Theyre sufficiently far enough away from the Rygi that they probably wont get screwed unless things get really bad, but they tend to be at the whims of the Ceredigions. They also show a moderate desire to perform raids against Ystrad Clud, since that would provide them with a nice batch of income.
Corieltauvi They and the Elmet share the unique distinction of being the only kingdoms along the coast of Morimaru[4], but Corieltauvi has the advantage of not being perpetually in fear of a Rygi invasion. They are generally close to the Rheged when it comes to raiding Ystrad Clud, but other than that they tend to get bullied by Ceredigion.
Aeron During the collapse of Gododdin, the southern Aerons managed to break free and form their own kingdom. The turmoil to the north caused them to seek refuge in the Cambrian Confederacy, and the Confederacy was willing to take them in. They wish to see the kingdoms of the Ystrad Clud join Cambria, but they havent exactly seen much success. Also, they are still seen as foreigners, having not been around at the Battle of Corieltauvi Ratae.
It should be noted that some kingdoms tend to be closer than others. For example,
Ceredigion,
Gwent,
Dyfnaint, and
Corieltauvi are all generally rather supportive of war against the Rygi (though fifty years of relative peace has calmed them down somewhat) and tend to favour a stronger navy, primarily due to the coastal locations of those kingdoms. Meanwhile,
Powys,
Dobunni,
Pengwern, and
Elmet tend to prefer not to go to all-out war with the Rygi, but would like to have a strong common army, just in case things turn sour.
[1] River Severn
[2] River Thames
[3] River Mersey
[4] North Sea