Following the destruction of the second Death Star and death of Emperor Palpatine... 

Grand Moff Gaunt Sevrann set about the task of restoring the power that had been squandered by the late Emperor.

Frustrated with the incompetence and inefficiency of the Admiralty, Sevrann elected to begin separating his own forces, securing the best and brightest for his own purposes. Quickly consolidating control over the former ISRG, the Grand Moff relocated his own base of power into the fringe worlds along the Galactic West, beyond the prying eyes of New Republic Spies.

When the "Supreme Commander" Rax demanded the use of Sevrann's own flagship, the Grand Moff complied with the request. Though formidable, the ship was not necessary to Sevrann's plans. By handing over control of this cumbersome, lumbering behemoth, Sevrann was able to secure full control over nearly a hundred smaller ships suited to his task.

By the time that the Disaster at Prakith spelled the final doom of the Empire, Sevrann had amassed for himself a hidden fleet consisting of the most capable warships and crews of the dying Empire. More important to his purpose were the tools, personnel and raw materials necessary to complete the various projects that had been set aside by the Emperor's sole fixation on the Eclipse and Death Star projects.