In the future, what was the United Nations has been succeeded by a new cross government alliance. Dubbed the Terran Supreme Council, or TSC, it was organized to present humanity's common front for the colonization and occupation of what was initially called "The Colonial zone", which represented more of a political promise than a scientifically determined area. With the passing of the Terran Colonization Act in 2053, the Colonial Zone was split into 7 sectors, each one named after a color of the rainbow.
At first, only private enterprise fueled the colonization efforts due to the neutrality laws prohibiting individual nations from claiming territory in space. This ended with the Terran Security Act of 2114, which ended the individual militaries of it's member nations and formed a united Terran Security Force responsible for the protection of all the members of the Terran Security Council.The act also allowed individual nations to claim territories in space. This act was largely the result of rumors of rebellious militia being allowed in the un-policed colonies, as well as reports of crime, unhappy settlers, and poor oversight by the corporations as to the activities of their employees. The Terran Security Commission was authorised to "fix" the problem by any means necesary.
The "fix" was supposed to be direct military oversight of every colony.
The colonists said no, and they said it with bullets.
The Succession Wars would be fought over a hundred years until the Treaty of Unions was signed in 2249, which left the TSC with control of Earth and the Solar System, The Taurus-Regnon System that served as a gateway between the Red and Orange Sectors (the planet Man Hunter e507 is stationed on is there), and the far flung Indigo Sector. The Indigo Sector would be combined with parts of the Blue and Violet sectors that had been purchased after the Treaty, and reorganized into the Indigo Frontier.
With the war now over and space now free of fighting, the colonial spirit has once again gripped Earth. "Flights to the Frontier" are becoming a right of passage for the new generation, as a war weary and overpopulated Earth looks to the stars to find its destiny.