The Oakheart Sovereignty are called what they are because that was the name of their first King - King James Oakheart - a simple and kind man who led his people out of the mists of the Sundering, to prosperity and strength in their new home, a series of closely neighbouring islands known to outsiders as the Fracturlands, but known to the Knights and Serfs of the Oakheart Sovereignty as the place where King James of the house Oakheart reigned - the Oakheart Sovereignty.
However, following the Sundering itself, an event that caused magic to permeate and fill the world and act upon it in unpredictable ways, as well as split the Earth and replace it with sky... their people were not the same. Indeed, the Oakheart Sovereignty were particularly affected by this, for they had been the closest of the Three Nations to the original source of the Sundering's magic - though they did not know that. Shortly after their establishment as the ruling force in the Fracturlands, they experienced the first and greatest impact of magic.
Any child born after the Sundering would not be simply male or female, but a human or a dryad, too. Within the first three generations, all of their women had become creatures from myth, whose lives were greatly extended, and bound to the souls of trees. Their skin became gently green around their hands and feet as they grew older, and their maintained a constant appearance of youth until their deaths - which did not come until their trees passed too. The trees also felt this change, however - many of them began to walk. The changes kept coming, their world slowly becoming saturated with the eternal and everlasting force of magic. There were dragons as well as the Ents, but also there were elves emerging amongst them, and fae and spirits too. They were the first people to come to grips with magic, bound either in artefacts or created by man - and it is a legend that it was from the Fracturlands that the first Sky Whales emerged.
But then, Sky Whales are just legends themselves.
In all of this change, the only things that did not become so different were the men. A few of them would go on to call themselves elvish, yes. Some would become wizards, true.
But most of them were unchanged entirely.
And so the greatest tragedy of all befell them - the King, as Kings do, died. His Queen did not. As if the death of their beloved monarch had not been enough, the Queen did not emerge from her chambers for weeks - and her children, Arthur and Arabella, could not bring themselves to speak of it.
But life goes on, and young Arthur became a great king too. Arthur Oakheart. In fact, the Oakheart dynasty continued healthily for many generations - until Jane Oakheart.
But that is a story for the Red League to tell.
The Oakheart military wears plate armour, and mail shirts. Their firearm technology is limited, but they make up for it with an excellently disciplined and skilled army of conventional soldiers, equipped with basic rifles, as well as longbows and swords. Their airships are heavily armoured and slow, but almost all of them are floatstone-based in their construction, permitting them to use the Upper Luft to move about the world. Their ace card, however, exists in the form of the Dragonriders, who ride dragons. These dragons are not small, they are big - big enough to tear smaller airships from the sky completely - and they spit fire hot enough to melt men alive. These dragons are also capable of surviving flight in the Upper Luft, permitting their riders to use them for devastating strikes with unprecedented range. The only thing that these knights cannot use this for is a surprise attack, however. That would be against their code of honour.
The Oakheart Dominion observes the feudal system, in which the Lords and Knights are in possession of all, and the serfs are in possession of none. Despite this, chivalry and generosity are the dominant traits of the nobility here, and nobody who works is allowed to go hungry. For this reason, the majority of the people are mostly satisfied with their lives. The seat of their power is Ethelon, the capital city and home of the current King, King Ralen Pinestock. He is an unmarried King and this does not sit well with the people, but is otherwise a peaceful and wise man with the potential for a long and healthy reign ahead of him. It is for this reason that, as long as Ralen Pinestock, last son of the Pinestock house, remains king, the Oakheart Sovereignty is unlikely to go to war. But there are those within the Sovereignty that plot against him - and more than that, the Oakheart Dominion are the strongest opposition to the rise of the Heavens' Eyes outside of the city of Solace, and though they remain relatively unaware of the true threat they possess, the Heavens' Eyes are already making plans to destabilise the Sovereignty. What's worse, his likely successor is a hyper-nationalist, likely to respond to the usual Dominion displays of strength, and the Red League's very existence, with war.