Mull Station is actually a derelict Venator-class destroyer lost during the Clone Wars. Although no official record of the station exists, it is well-known among ne'er-do-wells the galaxy over, and is 'owned' and ruled by the crimelord couple Obar and Seema Mull.
Mull Station originally began its existence as the Brotherhood, a Venator-class destroyer that saw much action in the Republic's war against the Confederacy of Independent Systems. But after a routine hyperspace jump, the Brotherhood never reached its next destination.
An investigation into the disappearance revealed no trace of the vessel, and when the CIS declined to take credit for its destruction, the Brotherhood was declared missing, and presumed destroyed in a catastrophic astrogation mishap.
Five years before the Battle of Yavin, a small-time crook and con-man named Nert Swineman was on the run from bounty hunters hired by his ex-boss, the petty Gran crimelord 'Two-Eyes' Kleet. Kleet's bounty hunters had caught up with Nert near a nebula called The Whirl, a giant, sensor-baffling gas cloud that lay just outside the Abrion sector. Faced with a choice between likely death in The Whirl and certain death at the hands of the bounty hunters, Nert sent his craft on a blind jump into the nebula.
Shortly thereafter, Swineman's transport was knocked out of hyperspace by the mass shadow of what turned out to be the Brotherhood, floating dead in space. Sensor scans revealed that the destroyer's engines were irreparably damaged, and that no life forms were aboard. Sensing an opportunity, Nert Swineman returned to the galaxy at large and contacted 'Two-Eyes' Kleet, offering the crimelord the Brotherhood in exchange for his own freedom. Kleet agreed, and brought his gang to the coordinates to pillage the vessel.
However, not content to escape with his own life, Swineman also secretly offered to sell the Brotherhood's location to Kleet's rivals, the Mulls, a human crimelord couple. The Mulls's gang sped to the site and attacked Kleet's forces while they were unprepared, devastating them and claiming the warship for themselves. They paid Nert Swineman handsomely and, when he asked if he could join their gang, pronounced him untrustworthy and had him executed, taking their money back before the petty swindler even had a chance to count it.
Upon its rediscovery, the Brotherhood was found to be completely un-flyable, its engines destroyed in some sort of massive explosion. The vessel has power, and its life support and artificial gravity systems function optimally. All of its computer records were found to be completely erased, however, which is extremely unusual (or as many would say, impossible).
The vessel still retains all of its many carried craft, though of course these ships and vehicles (with the exception of its ARC-170s, which have limited hyperdrives of their own) can't be brought out of The Whirl unless carried within the hold of another ship. The Mulls will transport some of the fighters to another system in this manner when a situation warrants it, however.
No trace of the vessel's nearly 10,000 crewmembers and troops has ever been found.
Under the watchful eyes of Obar and Seema Mull, the derelict vessel, now known as Mull Station, has prospered. Growing into one of the galaxy's best-kept secrets, Mull Station is a haven for those on the wrong side of the law. Part of its draw is that it would prove extraordinarily difficult for another pirate group to attack, as it still retains not only its formidable armament, but its original Clone Wars fighter complement as well. Because of this, the Mulls are always looking to hire hot-shot pilots and gunners.
However, two years ago, during one of the Mulls's many arguments, the criminal couple swore they wanted nothing further to do with each other. Unfortunately for them both, neither was willing to part with Mull Station. They each then vowed to occupy only half of the station and never speak again, even having their crews paint a great, black dividing line down the center of the vessel, from fore to aft. Obar Mull now occupies the port side of the station/ship, while Seema inhabits the starboard. Each holds court on their corresponding bridge.
For visitors to the station, this is more an amusement than any real barrier, but to the full-time population, it's actually serious business - since doing any kind of work for 'the wrong Mull' can get one spaced in the blink of an eye...
Mull Station and the EmpireEdit
Despite Mull Station's status as a shadowport, its existence and location are not as secret as some might hope. Through its spy network, the Galactic Empire learned of Mull Station some time ago, but as of yet have made no move to reclaim their property. The costs involved with removing and replacing the old Venator's destroyed engines, when compared to simply constructing a newer, top-of-the-line ship, have been deemed a frivolous waste of time and credits. Not to mention, the station provides a perfect location for Imperial spies to keep tabs on the comings and goings of wanted criminals, and suspected Rebels.
Both Obar and Seema Mull suspect the presence of Imperial spies on their station. However, they have chosen not to investigate the matter too deeply, lest they bring the wrath of the Empire down upon their beloved station, and upon themselves.