Each faction had their own goals and philosophy. The Harkbacks believed that the old Earth has not died, and the Empire - the most mysterious faction - believed that humans should stay in the Chain of Worlds.
Secretly the Emperor creates the Mechanical Spirit - a super mechanism to help him discover new Worlds. Only the Emperor's mortal foes the Spirits could discover new worlds, and that was the source of their power. But now the new time has come.