Vardus Praal - Istvaan System Compliance: One of the more notable campaigns carried out by Primarch Corvus Corax and his Raven Guard Legion during the Great Crusade was the Imperial Compliance of the Istvaan System in 994.M30, located in the northern reaches of the Ultima Segmentum, far beyond the established heartlands of the Imperium.Though cut off, scout vessels ranging ahead of Corax's 27th Expeditionary Fleet had found evidence that human life on Istvaan III had managed to maintain a largely cohesive industrialised society that had endured the millennia intact, making it a high priority for contact and absorption into the Imperium.The military forces of the indigenous Istvaanians, including the renegade psykers known as Warsingers, were professional soldiers who did not break easily, even when confronted with the might of Space Marines. There was some resistance, but the last elements of the aggressive faction, including the Warsingers, were destroyed by the Raven Guard at the Redarth Valley on Istvaan III.The Istvaanians kneeled as a defeated foe but were welcomed into the fold as men of the Imperium. Though they had waged war against one another, the Imperial Truth had prevailed and the Istvaanians had sworn to accept its teachings. By proving themselves men of wisdom and civilisation, they were deemed fitting partners for the many other worlds of the nascent Imperium.The established planetary capital of Istvaan III, the Choral City, was chosen as the site of Imperial power and with the help of the Imperial Army Pioneer Corps and Mechanicum oversight, bunker and barrack networks were constructed to house its sizable new garrison, and the wrecked Precentor's Palace was raised again as an Imperial Castrum-fortress to house the seat of government.Alongside this a star port was created to manage inter-orbital traffic, and the woefully inadequate defences reconstructed and fortified to required Imperial standards. Along with these developments came the usual procession of goods and technologies, as the agents of Imperial law, iterators and administrators flowed into Istvaan III, and an assigned Imperial Commander to govern the planetary system was installed.The Istvaan System had required force to impose compliance so an outlander was chosen rather than a local to rule, and this task was given to Vardus Praal, formerly a Major of the XIth Lastran Rifles and later career politician of the Ultima Segmentum Court. Given Praal's record both as a soldier and civil administrator, he was deemed a "safe pair of hands" to carry the responsibility of shepherding these millions of lives through the transition to becoming productive and loyal members of the Imperium, and initial records show he set to his new role with gusto and considerable success was met in the initial years of his tenure, but this was not to last.Conditions within the Empyrean in proximity to the Istvaan system grew steadily worse almost from the point of Compliance. Isolated as it always had been by distance from other inhabited spheres, it became increasingly difficult to reach by astro-telepathy and navigation as well. What reports that reached Terra, often relayed fifth and sixth hand from distant Expeditionary fleets and Rogue Traders on the periphery, and solar months old, spoke of a rising civil disorder, of iterators murdered and unexplained riots and outbreaks of mass hysteria in the cities.The blame once more was centred on backlashes from the natives after attempts to forcibly dismantle local sects, the most dangerous of which was given the name 'Warsingers'. Matters worsened as Praal ordered the garrison to tear down temples and breach the sealed vaults of ancient religious sites in order to break the subtle but deep hold superstitious fears had over the Istvaanians and bring them into the light of Imperial Truth, but as to the success of this nothing could be ascertained as the warp storms which blocked Istvaan from the Imperium's core worlds worsened and all communications ceased.Six years after the last official communiqué from Istvaan III, a Death Guard patrol ship on the outer edge of the Legion's fleet, near Neo-geddon on the very edge of explored space, picked up a faint echo of an Astropathic transmission from Istvaan III. Though garbled and incomplete, its central message was clear: Istvaan III was in open religious rebellion, the Imperial government had collapsed, and Vardus Praal, now turncoat and perhaps turned mutant or psyker -- the message was unclear -- was leading the revolt, and the streets of the Choral City running red with the blood of non-believers.The message was estimated to be at least two years old, possibly six, but it could not be ignored. For Istvaan III and its tens of millions to have rebelled from compliance was a mar upon the Great Crusade that could not be tolerated, lest such sedition and malcontent spread, but that an anointed Imperial Commander who had received his office by the writ of the Emperor himself led the revolt was a crime that demanded the swiftest and most resolute punishment possible. It fell to Horus, the Warmaster, to bring Praal and all of Istvaan III to judgement, and he publicly vowed to make a fearful, bloody example to all the worlds of the Imperium of the price of sedition. But what few knew or suspected at the time was that the Istvaan III rebellion had provided Horus with the perfect opportunity to strike the first great blow of his own rebellion -- a blow that would fall upon his own.