Long after the conclusion of the Galactic Civil War, the former Galactic Empire was reduced to a handful of backwater sectors in the Outer Rim Territories, collectively known as the Imperial Remnant. As the Galactic Alliance strengthened its control over the galaxy, Imperial Head of State Gilad Pellaeon sought to build a sufficient amount of order and stability so that the Remnant would survive long after his death. In addition to the many actions he took in pursuit of this goal, a new military unit of bodyguards was created to protect the highest ranking officials in the executive and legislative branches of the government. This special detachment of the Stormtrooper Corps was known as the Imperial Elite Guard; its soldiers were aesthetically separated from the rest of the stormtroopers by the gray markings on the shoulder pads of their armor.
A year after the outbreak of the Second Galactic Civil War, the Galactic Alliance faced an increasingly dire situation against the rebellion of Corellia and its Confederate allies. Darth Caedus, the Dark Lord of the Sith Joint Chief of State of the Galactic Alliance, was eager to add the strength of the Imperial Remnant to the Alliance's overstretched military forces. Caedus was also impressed by the shock troopers of the Imperial Elite Guard and their reputation as an equal match to Darth Vader's 501st Legion. By this time, the Elite Guard was stationed in Ravelin, the capital city of the fortress world Bastion.
After Pellaeon reluctantly agreed to help the Alliance in its objective to destroy the Corellian-led insurgency, a combined fleet of Alliance and Imperial warships converged on the secessionist world of Fondor. A unit of the Imperial Elite Guard accompanied Pellaeon and several high ranking members of the Council of Moffs on the Head of State's flagship Bloodfin. However, shortly after the battle commenced, the Galactic Alliance became divided after Joint Chief of State Cha Niathal betrayed Darth Caedus by accepting the Fondorians' surrender while her colleague was preoccupied with leading the attack. Though the vast majority of the Alliance fleet declared its allegiance to Caedus, Pellaeon's personal vendetta against the Sith Lord influenced his decision to support Niathal's backdoor deal with Fondor. As a consequence, Pellaeon was assassinated by former Jedi Knight Tahiri Veila. With the Head of State out of the way, the Moffs redirected Imperial forces to support Caedus and the true Galactic Alliance against Niathal's faction. Unfortunately for Veila and the Moffs, much of the Bloodfin's personnel were loyal to Pellaeon, and thus the Elite Guard found itself in a desperate fight to the death with mutineers. Although the Guard failed to prevent the deaths of the Moffs, their actions created a distraction that allowed Caedus to infiltrate the Bloodfin and rescue Veila, whom he anointed as his Sith apprentice.
In the aftermath of the debacle at Fondor, the remaining members of the Moff Council secured their hold over the Imperial Remnant. At the same time, the shock troopers of the Imperial Elite Guard served as protection detail for the Moffs. As such, they accompanied them to the Battle of Roche and also participated in the Battle of Uroro Station. Under the command of Tahiri Veila, a special detachment of the Elite Guard attempted to destroy the Jedi Order's secret base on Shedu Maad. However, they were forced to create a distraction against several Jedi opponents while Veila proceeded to complete the mission.
Yet their efforts were in vain. Shortly afterward, a disillusioned Tahiri Veila renounced her allegiance to the Sith Order and was taken into Jedi custody. Meanwhile, Darth Caedus was killed by his twin sister, the Jedi Jaina Solo. With Caedus' death and the surrender of the Moffs, the Galactic Alliance and the Imperial Remnant fell under the temporary control of the Jedi Coalition. By the end of the war, the Galactic Alliance remained as the dominant force in the galaxy and the Imperial Remnant was placed under the leadership of Jagged Fel.
- The Complete Star Wars Encyclopedia