Freedom is hard-won, but harder still to hold on to. The Free Union of Sovereign Worlds came together to defend themselves in the midst of a brutal war between our distant authoritarian rulers and a relentless aggressor, and have been fighting to keep that freedom ever since. In throwing off the yoke of the Ascendancy and earning the respect of the Dominion in battle, the Sovereign Worlds became the most recent of the four Factions to come into being.
The Sovereign Worlds lie distant to Sol and Terra, and encompass some of the most recently founded human colonies, as well as a host of other sophont species. The only thing that unites them is their commitment to self-government, and the cooperation that that commitment requires of them. Each member world has a representative in the Union Council on Concord, where the messy business of democracy and compromise takes place. The Free Union holds together more by the threat of conquest than any other factor, as the other Factions will likely exploit a world that tries to strike out completely alone.
The citizens of the Free Union are a diverse bunch. Although the majority of the population is human, there is a whole host of alien sophonts who live and work amongst them. The anarchic spirit that permeates the Union, though it is often a source of internal friction, also has its benefits. The Free Union of Sovereign Worlds has produced technological and social developments, and fostered MegaCorps that would have taken far longer to become established in more ordered and restrictive cultures.