Starting as a Jovian pirate king back when humans were still exploring ancient Sol. At the hieght of his career, as Legion was making its push for control of the system, Lord Callahan stole the Terran government’s biggest secret…The Vesuvius. The project was a massive starship, which, coupled with Stardrives stolen from the stranded Leven allowed Callahan and his first followers to leave Sol before Legion got a hold of themTerran
In the years afterward the Vesuvius traveled withing what would now be called the Core Worlds. at the time several small wars had sprung up that provided plenty of opportunity for Callahan’s mercenary pirates. He realized however that his ship was the first impression of humanity that the galaxy was going to get, so he formed the mandates of the Callahan Knights to insure that all of his people fought valiantly and justly. Soon after setting foot out of Sol, new races were incorperated into the ship’s crew…eventually whole ships joined the Vesuvius, creating the fleet proper.
The fleet’s first major opponent was the Matriarchy of Orion a Leven cluster of worlds just outside of Core Space. The Queen of Orion had declared her fleet and army to be an unstoppable. The Callahan fleet stoof againster her at half a dozen worlds and held her for over a year. The rivalry ran hot…but respect was had for both sides.
The Galaxy’s approving view of humanity was crushed when The Legion Empire began to spread accross the galaxy. An armada of cloned shock troops, genetic abberations, and infiltration robots stormed a dozen worlds in as may years, wiping out whole colonies without mercy, parlay, or remorse.
The Last known Callahan was killed in combat with the agents of Areis during The Apocalypse. Aries was hunting Chronos, and had tracked it to a planet named Gateway. Callahan Fleet, harried by the many fleets of The Legion Empire, and the Agents of Aries was cornered and routed. The Lord Callahan himself is reported to have died in personal combat with an agent of Aries and a Blue Vong.