The City has no true central government, no official national institutions or democratic framework.  Instead power is held by political entities called factions.  Some powerful factions compete for control of the City itself, while others are concerned only with material profits, and still others pursue more esoteric goals.  Some are benevolent, offering their services to all citizens of the City equally and asking very little in return.  Others are self-interested, serving themselves and excluding the public, or actively working against the public at large to enhance their own position.  Some factions are even more sinister, little more than organized crime families and thieve's guilds.  Many factions are public and well-known, others maintain a strict secrecy, with members publically denying the faction even exists.

No two factions are alike, and in fact any group or organization that becomes large or influential enough may come to be considered a faction, however loosely organized.  All factions have a few common characteristics, though.  They all have a goal, purpose, or guiding philosophy, a set of methods they use to achieve their goal, a leader (or a group of leaders), and membership requirements.  Many factions will also maintain an official headquarters, and will have very specific opinions of other factions, particularly those whose goals conflict with their own.

Players are encouraged to create their own factions if they wish.  There is no official list of factions, and no approval process.  Any you create in play are considered valid.  You're welcome to craft a Lorebook entry for your faction, but inclusion in the Lorebook does not make a faction any more "real" or "official" than any other.  Factions are subject to the same rules as characters and campaigns.  That is to say you may not create a faction that automatically imposes restrictions on other characters or factions or that is in any other way a form of power-gaming.  A faction's creator gets the last word on things such as membership.