The Union of Human Space
The Union is the closest thing to a “galactic government” at the start of the Exile War novels. It arose from the fact that wormhole FTL flights were risky. Some risk always existed that the wormhole might collapse, and the entire cargo be lost. When the value of a ship and its cargo exceeded the gross domestic product of most nations, operating an FTL flight without insurance in case of disaster amounted to madness.
Money Makes the Worlds Go Round
To insure those flights, the Union of Human Space came into being. Operators of wormhole vessels paid for a policy on every flight. Soon, though, the Union grew beyond that. When searches revealed a new habitable world, the Union would sell a policy that guaranteed one entity the sole right to operate insured flights to that world. Because the Union hated to pay for lost ships, its insurance policies required that FTL cruisers carry no dangerous substances. Soon the policies required ships to carry no dangerous individuals.
Soon the denizens of Human Space perceived the Union more as a government and less as an insurance company.
Behind the Scenes
For political theorists, I had a Dominant Protective Association, as described by Robert Nozick in Anarchy, State, and Utopia, in mind. A fictional world where humans colonize other worlds for the first time presents an excellent opportunity to imagine how the Lockean state of nature might really work. At the start of the series, the Union of Human Space represents a Lockean or Nozickian “Night watchman state.”