The Free Union of Sovereign Worlds was formed as recently as 3370 PT, and although it has survived for nearly five centuries, is still considered to be an upstart, barely coherent Faction by outsiders. In the lead-up to the formation of the Free Union, first contact with the Tulaki had occurred, and their invasion fleets were pushing deep into Ascendancy space. The Terrans had withdrawn much of their forces closer to the Sol and Trappist systems, which left the relatively new human colonies at the fringe of Ascendancy control operating virtually without support or oversight, under threat from Tulaki scouts and Elysian infiltrators, and retaining only nominal authority over dozens of alien vassal worlds. Without the threat of the Terran Navy backing Ascendancy authority and culture, their influence waned and alternative ideals gained prominence. After almost a century of being ignored and under threat, a group of 51 isolated human colonies turned to diplomacy to survive. In the spirit of desperation as well as cooperation, the Free Union was agreed as a compact between the 51 colonies and their vassals, to grant relative equality, representation, freedom and independence within an overarching confederation. The new polity swiftly press-ganged independant ship crews into service and fought a guerilla resistance against the oncoming Dominion fleets.
By the time the Dominion advance was blunted, the Free Union had built up enough military force to prevent its re-annexation by the Ascendancy, and a new Faction was born. In the centuries since its formation, the Free Union has expanded outwards, establishing new colonies as well as discovering new ones created by the great wave of Terran sleeper ships. They have brought many new alien species into their confederacy, swayed by the promise of an equal voice at the table.
Life on Free Union worlds is highly dependant on the situation on your individual planet. There is little oversight or applied cultural pressure on any one world from the Faction authorities. Some worlds are capitalist democracies, while others are feudal monarchies or authoritarian hives. Overall, there is a tendency towards egalitarianism and representation, and most worlds use some kind of voting by the majority of citizens - either for representatives or directly. Many aliens preserve their own individual cultures, older Terran colonies lean more towards bloody-minded independence, and newer discovered colonies may retain some of the trappings and attitudes of Pre-Fall Terra.
In play, the Free Union has the fewest “cultural requirements” of all the factions. Representatives of each group are expected to meet fairly regularly and keep each other relatively well-informed, but there is no real obligation to do so. A representative from the Union acts as a liaison between those present and the Free Union assembly, as well as having a mediation role between groups in dispute. Free Union “vassals” actually enjoy pretty much equal status in their Faction, but are usually perceived as being subservient to the humans by other factions. The Free Union as a whole does lean towards egalitarianism and collective decision-making, but not in a structured fashion across the civilisation. Individual teams or groups are free to develop their own internal structures.