Callisto
The Callisto Penal Colony was a space colony in orbit around the Earth which housing approximately 1,600 inmates. It was captured by the Free Fleet sometime in the 23rd Century.
Before the arrival of the Free Fleet, Callisto served as an orbital penal colony for dangerous Human criminals. Shortly after the Earth was hidden with the help of the De'rem, those left behind revolted and took control of the colony. Not long after the insurrection the colony was then captured by Commander Mezer Juul and its inhabitants were treated as live stock to be sold to the highest bidding alien race. In fact, 300 of the captured inamtes were sold to the Vonikin Krel.
However, before any more could be sold, another alien race, the Vendal attacked the Free Fleet. Caught in the middle of the conflict, the Terran inmates fought tooth and nail to survive lead by Captain Maddox Khan and Akari Lane. The tenacity and survival instincts of the Humans impressed the commander enough to offer them the opportunity to join the Free Fleet which all accepted in light of the undesirable alternatives.
Over time, through the leadership of Maddox and the training and resources of the Free Fleet, the former inmates became a feared and formidable fighting force known as the Omega Company.