Okay, I'm ditching the "Files" narrative as some of the details I want to include probably wouldn't be known by some Alliance officer.
IMPERIAL WARLORDS, PART II
The Empire of Warlord Zsinj
The son of a Fondorian mechanic, the man simply named Zsinj decided to follow in the footsteps of his mother and became an officer in the Imperial Navy. Quickly rising through the ranks, Zsinj was named the first Warlord of the Empire after leading a successful campaign against his mother, who had become a pirate and worked against the Empire. He was also made Grand Moff of the Quelii Oversector and used his power to quarantine the planet Dathomir.
After the Battle of Endor, Zsinj struck out on his own and built his own domain in the Quelii Oversector. The New Republic left Zsinj's domain alone for the first few years of its existence, instead focusing on greater threats such as the loyalist Empire still under the Imperial Ruling Council as well as other, more dangerous warlords. In time however, Zsinj's ambitions simply grew along with his empire, as those who had once followed Sate Pestage and Ysanne Isard were now falling under his banner. In 7 ABY, Zsinj made his first strikes against the New Republic, attacking major fortress worlds such as New Alderaan.
In response to these attacks, the New Republic organized a fleet commanded by General Han Solo to hunt down Zsinj. With the help of Rogue and Wraith Squadrons, the Solo Fleet was able to counter Zsinj's tactics with innovative maneuvers. After narrowly escaping several engagements with Solo's forces, Zsinj eventually retreated to his hidden base on Dathomir, only to fall into conflict with the Hapan Royal Fleet.
By 8 ABY, Solo was increasing all efforts to find Zsinj, not only out of personal vendetta but also as a result of the disappearance of Solo's son Ben. Han suspected Zsinj to be the one behind his son's vanishing and was determined now more than ever to find the warlord. After learning of Zsinj's location on Dathomir, Solo traveled to the planet and performed a strafing run on the Iron Fist, Zsinj's flagship. He then deployed concussion missiles onto the Star Destroyer's bridge, destroying the ship and killing the warlord.
Following the death of their leader, Zsinj's forces remained active for a time, albeit without direction. Some folded in with the Dark Empire that was fledgling in secret, while others fell in with other operating warlords. Zsinj's chief rival, Treuten Teradoc, was able to claim most of his fleet and declared himself High Admiral of the Mid Rim.
Lord Hethrir and the Empire Reborn
A native of the planet Firrerre, Hethrir was taken into the Empire and handpicked by Darth Vader for training as a Dark Jedi. Excelling his master's expectations, he was given the title of Procurator of Justice and put in charge of the Empire's criminal justice system. When the Empire fell, Lord Hethrir was already prepared for the event and led his followers into hiding.
From Crseih Station, Hethrir began building his army. Benefiting from the slave trade by supplying the thousands of prisoners he had kept on the station, Hethrir was able to buy armament from the gangster Reelo Baruk. Several Imperials fell under Hethrir's sway, including Admiral Galak Fyyar, who helped him outfit a fleet. Alliances with others warlords, such as Admiral Blitzer Harrsk, were also sought to help consolidate their presence in the galaxy.
In 12 ABY, Hethrir recruited the fallen Jedi Desann to his cause, making the Chistori his right-hand man and giving him the task of building an army of Dark Jedi to combat Luke Skywalker's restored Jedi Order. Meanwhile, across the galaxy the Empire Reborn set up installations and facilities under the New Republic's nose. At some point, the Sith of Darth Vorath became aware of the Reborn's activities but decided to leave them be, so long as they did not interfere with their own plans.
After a series of encounters with two New Republic commandos -- Kyle Katarn and Jan Ors -- Desann was able to procure the location of the Valley of the Jedi and took his Dark Jedi to Ruusan, where they used the Valley to bolster their powers, becoming the Reborn. Meanwhile, after learning of the Empire Reborn's existence from Katarn, the New Republic set out to investigate their activities, neutralizing their connections to Reelo Baruk.
Despite this, Lord Hethrir decided it was time to make his first move against the Republic by launching an attack on the Jedi Praxeum. By destroying the Jedi, Hethrir hoped to use it as platform to bring his empire to prominence. With Desann and Admiral Fyyar at the head, the Reborn forces were sent to Yavin 4.
Unfortunately for Hethrir, the attack did not go as planned. Having infiltrated the Reborn's flagship before it launched from Cairn Installation, Kyle Katarn was able to alert the New Republic to the Star Destroyer's location, and Admiral Fyyar was destroyed with his flagship before it could make it to Yavin. Katarn then headed for the Jedi Praxeum, which Desann and his Dark Jedi were already attacking. With Katarn's help, the Jedi were able to defeat Desann and his army.
After this major setback, Lord Hethrir retreated from the public eye, burying himself in his study to conjure up a new plan of action. Two years after the failed attack on Yavin, Hethrir was contacted by a Dark Jedi named Tavion Axmis. Axmis had been an apprentice of Desann's who had given the location of the Reborn's flagship to Kyle Katarn and fled to escape punishment from her master. Hethrir was about execute Axmis for her treason until she showed him an artifact she had purchased from a merchant on Commenor: the Scepter of Marka Ragnos, an ancient Dark Lord of the Sith.
Seeing a new window of opportunity opening before his eyes, Hethrir tasked Axmis with finding the Tomb of Marka Ragnos and resurrecting the ancient Sith in the hopes that it would give the Empire Reborn the leverage it needed against the Jedi and the New Republic. Unbeknownst to Hethrir, Axmis had already been planning on doing just that and had only informed him at the behest of one of Darth Vorath's Sith. Despite providing Axmis with additional resources, she was soon defeated by the Jedi Jaden Korr, who also destroyed the Scepter of Ragnos, entrapping the ancient Dark Lord within his tomb forever. Shaken by this second setback, Hethrir was still not ready to admit defeat.
Setting his eyes on children to kidnap and indoctrinate into his empire, he soon discovered that Senator Leia Organa Solo would be visiting a nearby system, accompanied by her three children. Knowing that the grandchildren of Darth Vader were sure to be strong in the Force, Hethrir was about to send his spies to retrieve them... only to be stopped by Darth Vorath.
Although Vorath had allowed Hethrir to build his empire without incident, he had only done so because it provided the New Republic with a large enough distraction while he built his own empire. Now that the Empire Reborn had lost most of its army, Vorath no longer saw it as something worth keeping; and he especially could not allow Hethrir to kidnap the Solo children, as he was also aware of the power they held. Rather than simply kill Hethrir however, as that would attract too much suspicion, Vorath instead broke the Procurator's mind, driving him mad. The Sith then left Crseih Station while Hethrir's madness prompted his followers to disband, not wishing to follow a crazy emperor as well as lacking the desire to press onward in his steed.
Following this, Hethrir was not heard from again until fourteen years later, when he was found on Belderone by Toah Jarsan's clone. Having received professional help for his madness, Hethrir was sane enough to tell the clone Toah of a secret he had kept from the entire Empire Reborn: the existence of Waru, the mastermind behind the Glorian Empire. Waru had been pulled from his universe by the intense disturbances in the Force Hethrir had caused with his torturing of prisoners and had served as a living conscious for Hethrir.
After learning all of this, the clone Toah went on to form a Dark Jedi Order to one day fight against the Glorians. Meanwhile, Hethrir lived the rest of his years on Belderone, eventually passing away in 31 ABY.