Orpheus Sector - The Orphean War of Faith: At the end of the 39th Millennium, the Orpheus Sector was trapped in a deep state of neglect, its defences overstretched and its planetary governments in political disarray. On Amarah Prime, the last scion of the sector's founding dynasty, the line of Orpheus, died out, and the sector's governance had passed to the dissolute House of Laan. Lacking the political acumen of other houses, the rule of the House of Laan over the sector was fragile at best, and ill-suited for the hardships to come.With the Haxan Wars still raging in the neighbouring Haxan Sector, the Orpheus Sector's military resources fuelled the Imperium's fight against the Apostate Hepstad and the Drukhari Slaughtervane Kabal. At the same time, the sector needed to tend to its own defence as both xenos -- the descendants of the Ork incursion of 160.M39 -- and Renegade raiders plagued the Drucillan and Deluvian Sub-sectors. Unable to keep these menaces in check, tensions over Imperial tithes and the cost of the ongoing war degenerated first into campaigns of petty vendettas and assassination, and later into outright civil war between entire worlds.Open conflict erupted when the honour-clans of the Drucillan Cluster overthrew their local opposition and declared their secession from the Orpheus Sector. The cluster's principal world, Drucilla Majoris, quickly becomes a haven for other Renegade fractions within the sector, posing an ever-growing threat to the region's stability.In the Deluvian Sub-sector, feeling threatened by its neighbours, the Parliament of Amraphel intended to conduct a preemptive strike against its rivals. Seeking to maintain deniability over its illegal actions against fellow Imperial worlds, the Parliament called upon xenos mercenaries to do their dirty work, only to discover that these mercenaries were in fact a splinter-web of the dreaded Khrave. The Khrave devoured the conspirators' minds and added Amraphel's rulers to their larders before using their influence to subdue Amraphel's population. As the number of mysterious disappearances increased over the following solar months, the Adeptus Ministorum uncovered the truth and lead the population in an uprising to rid Amraphel of the xenos taint that had befouled it.If all this were not enough, it soon became obvious that -- as in the Haxan Sector -- the malign taint of Chaos was the root cause behind a series of brushfire conflicts and revolts. To regain control over this precarious situation, Imperial Guard regiments needed to be brought in, but after several early successes, the Imperial troops encountered hordes of mutants fighting alongside the Heretics and rebels. On the worlds of Apollyon and Selakhar, the Guardsmen also encountered foul daemons. This encounter acted as a catalyst for the fractious ruling classes of the sector to put their own interests aside and unite, ultimately leading to the Orphean War of Faith.This conflict was sparked by the arrival of a person of great importance, Arch-Confessor Marduk of Helvamon, later canonised by the Ecclesiarchy for his vital part in the Orphean War of Faith. Led by visions of the God-Emperor Himself, Arch-Confessor Marduk had declared a War of Faith for the souls of the Orpheus Sector, his visions warning him of a terrible menace to the Imperium, "...rising where the light of Orpheus falls forever in shadows." In 903.M39, the ramshackle Marduk fleet arrived within the Orpheus Sector. Marduk's fiery orations, ecstatic visions and martial fervour had gathered a crusading force around the Arch-Confessor.This army, numbering many hundreds of thousands strong, was not merely made up of Imperial zealots or pilgrims, but also held many trained militia-men and even seasoned Imperial Guardsmen in its ranks. However of even greater strategic importance was the presence of the Arch-Confessor himself, as Marduk soon became a potent rallying point for those who opposed the forces of darkness.With the arrival of Arch-Confessor Marduk, the Imperial war effort gained momentum. In the sector's east, thus far untouched by the growing turmoil, countless ordinary citizens soon swelled the ranks of Marduk's crusading forces, inspired by the Arch-Confessor's vision and emboldened by his public speeches. One by one, the sector's secular and spiritual authorities rallied around the inspirational Arch-Confessor, and he led his crusade along the route now known as the Orphean Pilgrimage.When the baleful presence of daemons was confirmed and several warbands of Chaos Space Marines were conclusively identified, the Imperial Crusade was reinforced by contingents drawn from the Adeptus Astartes, the Adeptus Ministorum and the Inquisition. To counteract the corrupting influence of the daemons, the Ordo Malleus despatched a full taskforce -- believed by many to have also contained Battle-Brothers of the Grey Knights as well as Inquisitorial Storm Troopers and Inquisitors.The most numerous of these reinforcements were the Space Marines of the Angels Revenant, whose entire Chapter answered Marduk's call, and the Sisters of Battle of the Adepta Sororitas, whose contingents were drawn from the Order of the Valorous Heart and the Order of the Black Sepulchre. Despite this infusion of fresh troops, the Orphean War of Faith raged for nearly twenty standard years, ravaging the sector's economy and several of its worlds, until by 921.M39 the Chaos-aligned fractions had been pressed back to their fortress of Colkasth.On this former Hive World, the Chaos warband known as the Deathmongers had settled, their Warpsmiths turning the world into a living hell. Colkasth's population had been used as raw materials for their abominable plans. Former Imperial citizens had been warped by the powers of Chaos into living flesh-weapons, mutilated and insane cannon-fodder intended to fight and die in the battle that would follow. In contradiction to any sane military tactics, Arch-Confessor Marduk decided that his assault forces on Colkasth would be entirely human.He despatched his allies from the Adepta Sororitas and the Adeptus Astartes away from his fleet to harass, and destroy those Traitor elements already vanquished or retreating. Faithful to their oaths, they did not question the orders of the Arch-Confessor and thus the last battle of the Orphean War of Faith began without their aid. From the final communications received, it is known that Marduk's offensive met with initial success, the crusading soldier-zealots holding back the fury of the daemons with fire and faith and establishing several landing zones on the planet's surface before astropathic contact with the besieging Imperial army was abruptly lost.The first ship to reach the system after all contact with Marduk's fleet was lost was the Intercessor, an Adeptus Astartes Strike Cruiser belonging to the Angels Revenant. As soon as the Intercessor had cleared the system's Mandeville Point, the mighty vessel was attack by two unidentified, yet smaller vessels which proved extremely agile and powerful. It is largely accepted that the vessels neither belonged to the Imperium, nor to their Chaos opponents, and must thus have been of xenos origin.Severely damaged, the Intercessor remained victorious, destroying one attacker and forcing the second to retreat, but the Strike Cruiser was virtually crippled in return, its engines badly damaged. Reduced to travelling at a frustratingly slow pace, the Intercessor could only witness a great naval clash in the inner system on its long range Augurs, with the Angels Revenant powerless to intervene. Only solar hours later did the limping vessel reach Colkasth's orbit, where it found the world's cities and fortresses shattered, great parts of the world's surface engulfed in radioactive flame. The Imperial armada likewise lay in ruins, reduced to a great orbital field of burning debris and gutted hulks.The attackers were long gone, their motives and identity unknown. The Angels Revenant boarded the destroyed Imperial vessels in search of clues and discovered some scattered groups of survivors amidst the fleet's wreckage and the fallout-shrouded cinders of the world below. Those who bore the stigmata of Chaos the Space Marines immediately put to the sword, while those survivors who had fought for the Emperor the Angels Revenant carried to safety. Unfortunately, Arch-Confessor Marduk was not counted amongst these survivors and the priest was soon beatified by the Holy Synod of the Ecclesiarchy, an honour which warranted a change of name for the black, ash-shrouded world that would stand mute testimony to the Arch-Confessor's ultimate failure: Saint Marduk's Bane.