The Eternal War of Ideology
The Eternal War of Ideology, also known as the Eternal War of Ideas, the War of Belief, the Eternal War, the Forever War, or most informally, the War, or the Conflict, is an immense conflict that spreads all across the Sky River, many of it's satellite Gyres, four nearby Gyres, and occasionally, the Cosmic Abyss between them all. It is fought across both the Voidsea, and the Realmlands, and due to the limitations associated with the Realmlands, conflict in one place can vary dramatically from conflict in another.
Once, in ancient times, there was a time where the Sky River was considered a peaceful, mostly empty region of the Voidsea, with only a select number of Kinde that were capable of travelling to other worlds. Those days have long passed - Now, the Sky River is an immensely active region, with vastly inhabited worlds, tens of thousands of Kinde, colonies, anomalies, forces of nature and visitors from other Gyres - Cultures diverging, evolution going down different paths, and the emergence of Taekni, the Technopocolypse, and the discovery of the Realmlands only added further fuel to this powder keg. The end result is dozens upon dozens of Spheres, territories, independent archipelagos and Void Islands, creating a political climate that results in a state of near permanent conflict. To some, it is debatable if the myth of the peaceful Sky River ever truly existed.
Earning it's name due to the sheer number of conflicts which have broken out due to the incompatible philosophical, economic, and moral structures of many Spheres, the war is often regarded as an ideological one, though there were, as always, many different causes for the beginnings of outright conflict.
The reason for this is the sheer incompatibility between many Spheres - A great many find themselves fully unable to reconcile differences in philosophy, end-goals, and overall objectives. And whatever reasons kept these forces away from one another's throats have long since evaporated.
Not every Sphere finds itself in the conflict because it seeks a fight, but rather as a matter of either self-defence, defensive pact, or as recogneition that the other Spheres will not leave them alone. And with how quickly Spheres can rise and emerge, the state of battle is always changing.
Despite the name, the Eternal War is not one single conflict - Rather, it is a generalized, catch-all term, used to refer to a huge number of smaller, overlapping conflicts, both in the Voidsea and the Realmlands. In fact, most conflicts that break out are considered to be a part of the Eternal War, in one way or another. Indeed, it may be more accurate to think of each individual war within the Eternal War of Ideology not as a separate conflict, but rather a single campaign in a wider unending war. Many Spheres think of it in this way, as they find that doing so helps them to assess the geopolitical situation more accurately, and to figure out the moves of their rivals. This is used to assess everything, from military campaigns in different sectors, to diplomatic plays in the political core, to handing natural disasters and economic power plays. Diplomacy, alliances, truces and the likes are tools - Some can be permanent, others were never intended to be, and outright assassination is far from off the table.
Though the Eternal War of Ideology is a theatre within it, it is not a part of the Shadow War waged between the Valhallan Brotherhood and the Iron Decree. It is considered to be a theatre within it, with both sides infiltrating an Spheres they can to move things in their desired direction, but these are incidental to the Shadow War, and not exactly considered a direct part of it. The average fighter in the Eternal War has no idea about the Shadow War, though those who fight the Shadow War are very aware of the Eternal War.
Valhallan Brotherhood / Iron Decree Perspective
The Valhallan Brotherhood and the Iron Decree both share similar perspectives on the Eternal War of Ideas, though they consider it to be a distinct conflict to their own conflict, referred to as the Shadow Game.
In essence, both sides view each war as a microcosm of their own Shadow Game - The Cosmic Union engaging in a battle with the Twilight Imperium is a conflict that will send ripple effects through the Gyre, and that will serve their overall conflict. For example, groups that would go on to form both the Brotherhood and the Decree were involved in the Great Jovian War, waged between the Stjarna Union, Kuiper Confederacy, and the Titanic States of Saturn - The outcome of the conflict was one both sides had a vested interest in, and so, they participated.
Even independent Worlds, fighting their own wars between nation states, noble Houses, religious strife, societal and economic theories -The outcomes of these battles have consequences for their Shadow War - As such, despite not being a direct theatre for them, they are deeply intertwined in it.
However, it is important to note that their conflict did not begin with the Eternal War of Ideas, and nor will it end with it, lest one side be permanently eliminated. If the war ended today, the Shadow War would continue - This is why both sides view it as a theatre, but a distinct conflict to their own.
How the War Began
When the war began exactly depends on who is asked - Some might argue that it began in earnest with the foundation of the Cosmic Union, at the very start of the Valhallan Age. The conflicts that began in an attempt to contain this new emerging power completely shattered any pretences that may existed before that point, as each Sphere began to openly wage war.
Others soul argue that the conflict dates back before the Technopocolypse - Conflict was far from uncommon then, and some of those conflicts never even officially ended, such as the War of the Rouge Exo between the Jyrran Republic and the Inno Kingdom.
In truth, it might be more accurate to say that the war never really had an inciting incident, but merely a slow build-up that eventually exploded into open war, and could no longer be prevented. The situation fully deteriorated by the year 256 of the Valhallan Age (256 VA). This marked the point of near constant conflict with all neighbouring Spheres - Sometimes as mild as border conflicts, and some as major as entire offensive crusades.
Theatres of War
When looking at the conflict, it is important that one understands how the Voidsea and Realmlands interconnect with one another.
Though the Voidsea is able to support the existence of advanced technologies, like Void-Ships, long range weaponry, and the mechanical bodies that advanced AI Kinde require, The Realmlands does not - Or at the very least, no Sphere that currently exists understands the workings of the Realmlands enough to construct these machines within it. The Realmlands is also, by far, the fastest way to traverse vast distances between distant Void Archipelagos. Other issues, such as rival Spheres, environmental hazards, and tears in reality itself caused by Taekni, can make reinforcing a theatre difficult for just about any Sphere.
These factors combine to create situations where local forces may have to construct their own technology and naval forces - One theatre may have a vast array of Void-Fleets, able to jump from system to system. some may have to construct their own Void-Fleets based on the materials available to them in their system. Others may be forced to fight in trench warfare conditions, or with planetary vehicles such as those seen during the Gaian Age. All of this is to say that each Theatre has it's own unique conditions, it's on reasons for being the way that it is, and the method of conflict may vary from place to place.
The Voidsea
Both the largest and most diverse region of conflict, the Voidsea is home to conflict waged by Void-ships.
The Realmlands
The Realmlands are a very different battleground to the Voidsea - Yet it is still essential for the Voidsea's conflict. Technology within the Realmlands is limited, causing armies, armed with, Taekni, Traits, and cunning to guide the way there.
Spheres
The main fighting forces within the Eternal War are the Spheres.
The Cosmic Union is a Major Sphere. Located both in the Sky Riv
Twilight Imperium
The Consortium
Independent Worlds
For all the conflict found throughout the Sky River and the surrounding regions, there are still many worlds which have evaded becoming parts of any Spheres, for one reason or another.