|This article is about the the Imperial sector. For other uses of Orpheus, see Orpheus (disambiguation).
The Orpheus Sector was an Imperial Sector of Segmentum Tempestus. Its last Sector Governor was Calibron Laan. After a devastating Necron invasion, the High Lords of Terra declared its dissolution in 999.M41[1b].
Rogue trader Lady Arica Orpheus explored and catalogued the reaches of the galactic southwest in mid-M30. The area contains many aged stars, dead worlds, and celestial hazards that limited her exploration. Records in the great libraries of Terra make reference to sinister pre-human ruins and monuments on those dead worlds.[1a]
During the Horus Heresy, the savage civil war saw the regions of the sector under control torn apart by lawlessness and anarchy. Neither the forces of the Emperor nor Horus controlled the region. During the bloodshed of the Scouring, the Alpha Legion warlord Dynat Mal fled to the Sector's Mandragoran Stars. Dynat's forces, known as the Shadowed Ones, employed guerrilla tactics and dark forces to take over much of the region. This sundered realm eventually became known as the Dark Marches.[1a]
The Orpheus Sector was not formally established under after the Age of Apostasy, when Segmentum authorities launched a series of crusades. The most successful was the Dark Marches Crusade under Lord Tempestus Hal Orpheus, which brought over six hundred worlds under the rule of the Imperium. The arcing band of space was subdivided into four sectors: Haxan, Leyak, Eurydice, and Orpheus. The aging Hal Orpheus, kept alive only through the arts of the Adeptus Mechanicus, became the first sector governor, ruling from Amarah Prime. Favoured Imperial Guard regiments received Arcantis, Gedrid, and Midwinter, while the Adeptus Mechanicus received Myre in perpetuity[1a].
In 976.M37, all contact was lost with Leyak Sector. In response, the Orpheus Sector authorities increased their military tithes, constructed orbital defences, and forbade colonial expeditions into the Veiled Stars on pain of death. These restrictions increased civil tensions in the sector. Authorities brutally suppressed riots, rebellions, and cult activities across the sector. When the Black Crusade of Von Mallas the Transgressor reached the sector in 113.M38, it caused further uprisings on Colkasth and Epirus, draining resources required to fight the Transgressor's forces. Morros Lachrymal was founded as a penitentiary world to hold the rebels, but the fighting had ruined Epirus, which would take decades to recover even a shade of its former productivity[1a].
The Celestarii cult came to prominence during the civil unrest. Adeptus Arbites and Ordo Hereticus forces suppressed it wherever they could but they could not completely stamp it out. The Celestarii rejected the Imperial Creed and venerated a superior race that would bring eternal life to their loyal servants when they awakened. The cult took xeno-archeological remains from across the sector as their sacred relics and secretly carried out cannibalistic rituals[1a].
A sudden and mysterious attack struck the agri-world of Tlaloc in 889.M38. A squadron from Battlefleet Orpheus found the world annihilated with no intact bodies or recording devices to tell them what enemy had destroyed the world so swiftly. The Lord Commander declared the world under permanent quarantine while Inquisitor Kussan of the Ordo Xenos believed the Dark Eldar were responsible for the attack.[1a]
After nearly a thousand years of strife and warfare, its worlds bleeding resources to fight wars elsewhere and reinforce the sector capital's defences, and infighting amongst sector nobility, the Orpheus Sector erupted in civil war. Rebels in the Drucillan Cluster overthrew the government and declared their secession from the sector, rallying other rebels to their cause and undermining the sector's stability. The parliament of Amraphel hired xenos mercenaries to fight their enemies, only to become the victims of the Khrave they had hired. Imperial authorities learned that the Great Enemy had orchestrated most of the unrest.[1a]
In 903.M39, hope came to the fractured sector in the form of a crusade fleet. At the head of the fleet stood Arch-Confessor Marduk of Helvamon. Marduk declared a War of Faith for the souls of the Orpheus Sector, claiming to have received a warning from the God-Emperor himself of a great and terrible threat to mankind rising from the darkness of the sector. The Arch-Confessor provided a figurehead and a rallying point for the resistance against the dark powers. By 921, the Imperial forces had effectively destroyed the enemy, with only one holdout on Colkasth. The Angels Revenant strike cruiser Intercessor investigated the sudden cessation of Astropathic communication with the ground forces: two extremely powerful xenos void craft ambushed it on the edge of the system, but Intercessor destroyed one and drove off the other. The damaged ship can only watch a raging battle in-system via long-range auguries and by the time Intercessor reached orbit, the attacking force has fled, leaving Colkasth a burning, irradiated wasteland. The Angels Revenant sorted out the few survivors and the planet was renamed Saint Marduk's Bane.[1a]
In 819.M41, a contagious madness spread across the Industrial World of Chemarium II. The Chaos Lord and self-styled "Beggar King" Ranker Nonesuch led his insane followers to destroy Imperial manufactoria and slaughter Imperial forces. Nonesuch then spread his uprising to the rest of the system. Inquisitorial Stormtroopers were dispatched to aid the suppression campaign while an exclusion zone was established around the system.[1a]
In 990.M41, a sudden shockwave through the Warp extinguished the turbulence that had plagued the western Orpheus Sector for three centuries, causing celestial instability across the region. Astropaths, psykers, and witches across the sector went mad or simply dropped dead. Many void ships were blown off course or destroyed. Panic and mass hysteria gripped the Drucillan Sub-sector. At the same time, the Adeptus Mechanicus reported that the binary stars of the Caracol system unexpectedly went supernova. The Ordo Malleus believed that the events were precursors to a major daemonic incursion into the region. Imperial authorities ignored the Caracol supernovae, deeming the matter insignificant.[1a]
In 3716991.M41, a sudden and utterly unexpected invasion swept dozens of worlds across the sector. This was the beginning of a massive invasion by the Necron Maynarkh Dynasty. In 995.M41, the Orphean War reached an untenable stalemate that saw Imperial forces besieged and cut off but nonetheless holding portions of the sector. Necron forces became bogged down against the unexpected arrival of Chaos warbands and Imperial authorities estimated that the Sector would need a large crusade to save it, which could only be launched within thirty to fifty years minimum.[1c]
The Carta Imperialis File Register of 2231990.M41 lists the following principal celestial domains of the Orpheus Sector[1a]:
- Capitoline Sub-sector
- Deluvian Sub-sector
- Drucillan Sub-sector
- Eleven secondary administrative regions
- Seven exempted divisions
- Amarah Prime — Sector Throne-hold, Hive World, Fortress Imperialis, and principal fleet anchorage of Battlefleet Orpheus.
- Amraphel — Imperial world
- Apollyon — Ecclesiarchy world
- Arcantis: Imperial World
- Aryith — Feudal World
- C'syn'ad — Relic World/Astropathic relay station
- Chemarium — Industrial World (Ongoing civil war)
- Decapolis — Hive World
- Drucilla Majoris — Imperial World
- Epirus — Agri-World
- Harrow Watch — Adeptus Mechanicus Observation station
- Hydroghast — Agri-World
- Gorgon Quintus — Death World
- Khesd — Feudal World
- Libethra — Former Homeworld of the Angels Revenant, currently destroyed[1c]
- Lysmarchus — Fortress World
- Midwinter — Industrial World
- Morros — Penal World
- Myre — Forge World
- Pallasite — Frontier World
- Patara — Feral World
- Ribasu — Hive World
- Selakbur — Frontier World
- Saint Marduk's Bane — Imperial World
- Thamyris — Abandoned World
- Tlaloc — Quarantined World/Death World
- Altun — Dead World
- Caracol — Dead World
- Cutlar — Dead World
- Nightshard — anomalous celestial mass
- Uxmal — Dead World
In addition to the above, the sector contains 57 minor systems not notable.
- 1: Imperial Armour Volume Twelve - The Fall of Orpheus