Over fifteen thousand standard years, the Quietude had survived the traumas of the era by merging themselves so completely with their advanced technology -- as a result of possible xenos influence -- that there was little left of them that could be considered truly human.
The Quietude lived in vast and deep techno-hive cities protected by an artificially-extended icecap on their unnamed homeworld, an otherwise lifeless planet. They were encountered by the Imperium of Man's 40th Expeditionary Fleet near the end of the Great Crusade in the late 30th Millennium, and utterly annihilated in a short campaign as yet another of the Abhuman pretenders to the human future wiped out by the forces of the Emperor of Mankind.
Near the end of the Great Crusade, some time before the Council of Nikaea, the 40th Expeditionary Fleet encountered the Quietude. The Quietude were immediately hostile and had attacked the 40th Fleet in two separate actions, attempting to drive it out of their space. In the second of these actions, the Quietude captured the crew of an Imperial warship. The Quietude then ignored an Imperial ultimatum to cease hostilities and return the crew, instead subjecting them to torture and vivisection to extract information.
The Quietude claimed the information extracted from these unlucky subjects "proved" that the Imperium were simply pretenders to the heritage of Mankind; and that when the Age of Strife ended the Olamic Quietude would return to the wider galaxy and take their rightful place as the true inheritors of the human future. Naturally finding such a contradiction of the Imperial Truth unacceptable, but evenly matched by the formidable forces of the Quietude, the 40th Expedition grudgingly called for the aid of the Space Marine Legions in the form of the Space Wolves' 3rd Great Company ("Tra" Company) to assist in the assault on the Quietude's homeworld.
The Space Wolves began the attack by assaulting the orbital facility above the planet, and despite the Quietude's martial reputation and advanced technology, easily overcame the formidable onboard defences composed of gracile and robust cybernetic troops. The 40th Expeditionary Fleet then began an orbital bombardment of the planet below, which proved ineffective against the ice caps that the Quietude had extended over their hive cities.
Imperial Army ground forces found the going much more difficult when they landed, despite being supported by Titans and super-heavy tanks, with the strange lamp-like beam weapons mounted on the Quietude's defence towers extracting a heavy toll from the Imperial forces. After sustaining heavy casualties, the Imperial Army forces were withdrawn on the request of the Space Wolves, much to the anger of the Imperial Army commanders involved in the assault.
Instead of another frontal assault, the Space Wolves used the vast orbital facility they had captured to unleash an orbital bombardment. Forcing the space station out of its orbit, it fell into the world's atmosphere and smashed into the Quietude's cities with the power of tens of thousands of nuclear weapons, breaking through the ice shields and inflicting cataclysmic damage.
This unconventional assault was followed by a full scale attack on the now-burning cities from the combined Astartes and Imperial Army force that brutally eradicated the Quietude and purged all trace of their presence from the galaxy. It was later discovered that the orbital space station or "Instrument" as the Quietude called it that the Space Wolves had dropped on the planet was, instead of a weapon or military base, a vast archive that contained the last record of all Quietude culture and technology, causing it to be lost to Mankind forever.
Physiology and Anatomy
The technological level of the Quietitude was very high, at least equal to, if not more advanced than, that of the Imperium of Man. The people of the Quietude could barely be considered human by the time they were encountered by the Imperium; through ritualised surgery from an early age, they incorporated cybernetic enhancements into their bodies even more completely than the Tech-adepts of the Adeptus Mechanicus. By the time a member of the Quietude reached maturity, the only remaining organic parts of their body were the brain, skull, eyes, and spinal column. These biological components were kept alive within a purple nutrient fluid pumped through their bodies like blood from the powerful humanoid robotic chassis.
Citizens of the Quietude wore silver electronic hoods over their "heads", and instead of faces had holographic masks that displayed an image of a human face that could display different facial expressions such as anger. Underneath this, visible when their bodies shorted out due to damage or death, was simply a fleshless skull, eyeballs staring from lidless sockets.
Little is now known about Quietude culture, but it is believed that they were very mechanistic in both their modes of thought and operations. They were interconnected to each other and to their technology by a vast digitial social network that allowed each member of the Quietude to very quickly assess threats and provide the best possible response to them. Despite having replaced most of their organic bodies with cybernetic forms, the Quietude considered themselves to be both the epitome of human development as well as the only rightful heirs to the human future.
They found the defenders of the Imperium of Man to be repugnant pretenders to this mantle despite their origins on the human birthworld of Terra, and when first contact with the Imperium was made, the people of the Quietude did not hesitate to initiate brutal hostilities to wipe away a threat to what they saw as their own human ideal. In this way, the Quietude was a mirror-image of the Imperium of Man itself.
The Quietude's technology and deadly efficiency in the arts of war allowed them to survive through the turbulence of the Age of Strife. Apart from their space fleet, they possessed three main types of highly advanced cybernetic warriors. The smallest and lightest were the "graciles," roughly equivalent in size to a normal human but far more deadly due to their cybernetic enhancements. The "robusts" were larger, at least the size of Space Marines. "Super-robusts," the elite of the Quietude's military forces, were enormous two-headed and four-armed cyborgs twice the size of the robusts armed with a variety of close combat weapons including hooked tulwar blades and huge kinetic hammers. The super-robusts could be driven into a close combat berserker frenzy by stimulants injected into their organic central nervous system by their robotic bodies. All of the different types of Olamic warriors had highly advanced sensory systems.
Olamic warriors carried advanced weaponry as well. Most had Gravity Rifles that used a powerful gravitic pulse to propel an ultra-dense projectile at incredible speeds which could easily smash through Power Armour. They also carried fusion-based heat beams, perhaps similar to Melta Weapons, that made no noise except an explosive crack from whatever they hit. The Olamic super-robusts' Kinetic Hammers were similar in effect to an Imperial Thunder Hammer and could slay an armoured Astartes in a single, titanic blow.
All Quietude warriors were armoured by overlapping plates of woven steel, and emitted gravitic force fields whose potency and maximum points of strength could be quickly adapted to maximise protection against different types of threat. The Olamic warriors' humanoid bodies were generally resistant to any damage that did not compromise their remaining biological components.
The Quietude homeworld was protected by a heavily armed and well-protected orbital facility known only as "the Instrument" that was perhaps the size of a small moon, and embedded within a titanic graving dock. Their ice-shielded cities on the surface of the world were defended by towers bristling with powerful energy weapons that could destroy heavy tanks and massive numbers of infantry in a single blast, and by vast numbers of gracile and robust cyborgs.
- Prospero Burns (Novel) by Dan Abnett, Ch. 5