A hundred years ago, all of charted space was dominated by The United Leagues of Earth. The Antimatter Crisis changed that. Unable to supply power to the wormhole stations linking its outermost colonies, Earth was forced to grant autonomy and effective independence to numerous star systems, bringing into being a myriad of new nations among the stars. Now the Outer Systems are locked in a tense cold war, even as human society is shaken by the discovery of sapient alien life.