Southern Sphere Secession War

The Southern Sphere Secession War, also known as the War of Independence in the southern Human Sphere, was a major interstellar conflict fought between the Ordic League and various rebel groups in the southern Human Sphere that eventually coalesced into the Southern Colonies Alliance. Lasting over 30 years, the war is typically recognised as beginning with the Battle of Granitsa in 24 BT and lasting until independence was granted in 5 AT. The first major interstellar war fought by humanity on such a scale, the Secession War caused a major impact on human history and also saw humanity's first contact with non-human intelligent life.

In 45 BT, the planet Hongmu was first colonised, opening the Northern Frontier. The relatively more hospitable planets soon discovered in the north began a 'rush to the north' amongst the colonial powers, and many prior efforts to develop the harsh Southern Frontier planets were abandoned in favour of moving resources and manpower towards the north. When the colonial powers left, megacorporations stepped in to fill the governance and security void, picking up resource extraction efforts in order to profit from sales to the colonial powers' northern development efforts. Conditions in the Southern Frontier began worsening more than they already had been, and various insurgent groups started to emerge from frontier militias. Protests against work conditions and brutality began breaking out across the Southern Frontier, culminating in a mass uprising on Serenia that grew into a planetwide revolution. By 24 BT, after years of low-level insurgency, the revolutionary militias were powerful enough to challenge the corporate armies at the Battle of Granitsa. This was the first major victory for revolutionary forces and the start of open war between the revolutionaries and the colonial forces.

As the rebel movements made great advances against the corporate forces, they formed the Southern Colonies Alliance in 20 BT and began actively fighting against corporate and colonial forces throughout the region. By 16 BT, the rebels had fully liberated planets like Serenia and Frontera. The situation had deteriorated to the point that the Ordic League decided to step in directly, deploying large amounts of troops to the southern frontier to maintain their control over the colonies and contain the spread of revolutionary sentiment. The war quickly devolved into a difficult guerilla war both in space and on the ground, with neither side gaining ground through conventional warfare, though the colonial forces were clearly losing the propaganda war. Finally, in an effort to end the revolution once and for all, the Ordic League decided to make an example of Serenia in an overwhelming show of force. On 10 Hachigatsu (24th July) 0 BT, Ordic warships arrived at Serenia and unleashed nuclear weapons across the entire planet, carrying out the Serenian Terracide.

Instead of stifling the revolution, the destruction of Serenia only caused great anger across the entire Human Sphere, resulting in support drying up for an already unpopular war and millions of supporters moving to the southern frontier to join the revolutionaries. In the same year, due to events linked to the Terracide, the Aggressor Race also appeared at the edge of human sphere, dramatically disrupting the fighting. After a few years of ineffectively attempting to fight the Aggressor Race and the insurgency, the Ordic League decided to grant the Alliance the independence they sought, while pulling back their forces to fortify the cradle worlds in preparation for the Race attack. The Southern Sphere was granted independence in 5 AT, ending the Secession War.

Transfer of sovereignty
In the decades leading up to the First Extrasolar War, revolutionary sentiment was already stirring in the southern colonies, which were often poorly developed by the colonial powers and treated as expendable resource nodes. Conditions worsened due to the Northern Surge, whereby a large amount of profitable colonies were founded in the northern Sphere, leading to corporations moving capital and resources elsewhere at the expense of the southern colonists. Some colonies were still obliged to pay taxes to Ordic powers despite this, and few were represented at all in any of the colonial governments or the Ordic League. A low level insurgency called the Colonial Insurrection was already going on for several years, though the vast amount of rebel groups were mostly unconnected and operated in isolation, including some groups on the same planets as each other. Several of these rebel groups found their roots in rebellious colonial militia groups formed to protect against wildlife and bandits.

A turning point in the Insurrection was marked by the Iskandar Revolution, on the barely-habitable planet Iskandar. Populist leader Harrison Khan emerged amongst the working-class population amidst a major food crisis allegedly engineered by Donaumetall Iskandar, an Ordic megacorporation. Inciting local mining crews to revolt, Khan was able to defeat the PMC forces deployed by Donaumetall Iskandar and seize the terraforming centres, effectively taking over the planet. Iskandar became the heart of the revolution, and several of the largest militia groups met at Iskandar and formed the United Front for Popular Resistance, inviting local groups to join. Introducing a chain of command and organisation to the wide array of rebel cells across the region enabled the UFPR to incite a mass rebellion across the entire southern frontier.

Early guerilla warfare against the colonial powers' corporate military forces was effective, and within the first year the UFPR was even able to cobble together a space fleet that was able to challenge the corporate forces in space. Popular support for the UFPR in the colonies enabled them to seize large territories early on. However, the war took a turn for the worse when the colonial powers, through the Ordic League, chose to step in with a massive peacekeeping force. The technology gap between the UFPR and the colonial powers was very obvious as the Ordic nations' national forces tore through the rebels. In a few weeks, the rebels' positions were quickly overrun and the war devolved into a guerilla war once again. Finally, the Ordic League carried out Operation: Black Sky, which involved a mass nuclear bombardment of Iskandar, rendering the surface entirely uninhabitable. The few UFPR leaders still alive surrendered, and Harrison Khan was publicly executed, though the latter act was not made known to those living in the cradle worlds and Ordis. The remnants of the UFPR fleet fled into deep space, becoming known as the Remnant Fleet.

Following the end of the war, the colonial powers themselves stepped in to police the colonies, transforming many colonies into police states that were continuously besieged by guerilla activities. However, this only bred discontent in the local populations, and underground resistance groups began growing in number. Former rebel leaders and a new generation of revolutionaries meticulously planned the next colonial uprising, uniting the various resistance groups as the Second United Front. Fifteen years later, the Second Extrasolar War would be launched by the SUF, finally attaining the colonies independence, albeit partly due to surprise external factors with the appearance of the Aggressor Race.

On Ordis, the First Extrasolar War resulted in political turmoil which led to the Third Varunan War. The defeat of Yashima in this war resulted in the exile of the Yashiman government and military leadership to the colonies, eventually leading to the foundation of the modern Neo Yashiman Empire.