Brief background

About ten thousand years ago, a dynamic faction from a previously obscure star system began a crusade to push its ideology across the 27 million star systems of humanity. This faction, called the ‘Federation of Xah’, seemed unstoppable at first, utilising technologies unseen since the before the cataclysm that ended humanity’s golden age. Eventually, factions arose to challenge the hegemony of the Xahians, and despite initial conflicts that laid entire solar systems to waste, an uneasy cold war settled across the whole of human occupied space.
Over half of humanity, 700 trillion people, now toil under the authoritarian boot of the Federation of Xah, a totalitarian regime that seeks to use eugenics and population control to transform humanity into a more enlightened form. To better prevent a recurrence of the horrors of the past. The Xahians utilise a strict caste system, and demand total obedience from their subjugated peoples, offering a hope for the future that many see as merely an excuse for the crimes of today. Its unique Warrior caste, few in numbers compared to its opponents, enable the Federation to keep a lid on ever-fermenting dissent.
Their main opponent is the Northup Alliance. Once a loose confederation of systems seeking to hold off Xahian expansion, now a democratic republic, where system autonomy is second only to the never-ending needs for a strong military. Every conceivable political state, from hyper-capitalists to religious fundamentalism, to die-hard communists, all attempt to cooperate on a stellar scale. A vast bureaucracy and a political system that attempts to bring control to a population measured in the trillions, mean that for most of the population, the Alliance is a distant overlord with minimal authority. It lags in technology behind its rival, but can boast a military many times its size, and the two parties are more carefully opposed than either would like.
For those factions that fall outside of these two superpowers there are two options; balance careful diplomacy between the two or hide and hope to escape notice. Neither tactic is ideal, and the names of many once powerful organisations have been forgotten after their annexation. The galaxy is large, however, and humanity continues to expand, with new civilisations springing up every year, people desperate to escape the approaching Armageddon.