The Ironside Campaign began with the aspiration of being a short expedition requiring a dozen regiments and a half-dozen ships in an effort to reclaim a portion of the Imperium that had declared itself independent from the Emperor's rule. The Helios sector was comprised of a dozen worlds, its main industries being focused on three of its core worlds and viewed as being only able to muster a limited defence against the might that could be brought to bear. These assumptions, however, were proven to be absolutely inacurate.

The fleet, which had taken over two hundred years to reach the edges of the system, quickly found that the sector had not spent that time sitting idly awaiting their arrival. The outer areas of the sector were mined with hundreds of thousands of space mines capable of destroying most Imperial vessels with but one detonation. Three quarters of the invading fleet were destroyed as they exited the warp, the remaining few being destroyed by the battle stations the sector had built should their first line of defence not prove sufficient. The remaining ship, the Emperor's Star, fled back into the warp to return to their base of departure with the news of the fleet's destruction. When the ship arrived it was barely space-worthy, whole sections of the ship were open to the stars, its engines barely managing to bring it within range of the station. The remaining crew were quickly brought aboard the station for immediate debreifing.

Even before the ship was repaired enough to be capable of traveling in-system, let alone battle-worthy, a new fleet was organised. This fleet was comprised of over three dozens Imperial ships and nearly twenty seven regiments from the Imperial Guard were mustered to participate in what was dubbed the Ironside Campaign. Among this fleet were five Adeptus Astartes frigates from the Storm Eagle and Aurora chapters containing another three companies of the Emperor's finest warriors and all of their supporting equipment. The fleet immediately set course and were determined to return the sector back to the Emperor's light regardless of the cost.

The fleet arrived in the sector to the arrayed guns of the outlying defences that had destroyed the first group of ships. Aware of their presence and prepared the fleet eventually made their way past, leaving only a handful of ships as vaporised hulks floating through space. The first world fell quickly the crusaders, its defences thin and weak. From tactical observations it was determined that this planet had been the major source for the system defences and its population had been moved off-world to another planet within the sector to bolster its defences rather than to waste them futilely defending a planet whose main plan centered around the production of the outer defences. The next world proved not to be so easy. In a three year campaign on the planet it was finally subdued and returned to the Imperium.

It was during the war on the second planet that orders were sent requesting the assistance of the Officio Assassinorum. The Callidus Temple accepted the request and sent one of its assassin teams from the secretive Project Nemisis in an effort to demoralize the sector's resistance its target was determined to be the Planetary Governor of Latharsis, the inspirational head of the successionary forces. The Callidus Assassin team quickly made planetfall, the two women quickly inserting themselves into Latharsis society and positioning themselves near the planetary governor and his aides.

Eventually the two assassins were in a position to deliver their deadly biological cargo. The pair seduced the governor and virtually all of his command staff individually and introduced their infectious viral agent among them. The planetary governor and his command staff did die from the virus, however, so did nearly twenty five per cent of the population of Latharsis and other planets in the system. The virus also infected crews of the Imperial fleet and soldiers of the Imperial Guard when they landed on the infected planets. The viral agent that had been implanted within their very DNA prior to insertion had mutated while in their bodies and had taken a virus capable of nearly instantaneous death but no infectious properties from the infected subject to a full scale plague among the planets of the Helios sector. The viral infection on Latharsis, itself, was so strong and rampant that the planet was quarantined and plasma bombed from orbit in an effort to stem any further infection.

The degree of infection and relative inaccuracy of the research surrounding the Nemisis Project resulted in the immediate termination of it, the execution of nearly seventy thousand members of the Imperial Navy and Guard, the loss of eighty billion lives on Latharsis, and another sixty three billion lives on the other worlds within the Helios sector. The remaining members of the Nemisis Project's active field agents were recalled from active duty and summarily executed.

Compiled by:
Adeptus Nagal Preatus
In accordance with the Pax Imperius Schola