ONE SUN, MANY IDEOLOGIES
By the close of the twenty-first century, humanity had established permanent colonies on several extraterrestrial bodies in the Sol system, including Luna, Mars, and several of the Jovian Moons. Over the next several decades, colonies on these celestial bodies grew substantially, becoming breeding grounds for ideologies different than those of the United Nations on Earth. By 2160, these differences in ideals erupted into warfare, spurring several conflicts across the Sol system and culminating in the Interplanetary War, a six-year war that eventually ended with the newly-formed United Nations Space Command forces gaining total military control over all colonies in the system.
THE FINAL FRONTIER
In 2291, two theoretical physicists, Tobias Fleming Shaw and Wallace Fujikawa, unveiled the most influential technical achievement of the century: The Shaw-Fujikawa Translight Engine, the first human device able to travel faster than the speed of light. With it, humans were finally able to expand beyond their own star and begin colonizing the galaxy, which they did in great numbers through the second half of the twenty-fourth century and most of the twenty-fifth. Between 2362 and 2475, humanity colonized over eight-hundred worlds, greatly spreading their reach and lessening the population stresses on Earth and the Sol colonies. The rapid expansion of new colonies, however, brought renewed conflict between the central government of Earth and the increasingly disillusioned colonists who wanted more autonomy and freedom. By the end of the 2400s, insurrectionist groups would have formed in many of the new colonies, spurring a new violence that would claim over one million lives by the time first contact with the Covenant was made in 2525.