Segmentum Tempestus - Notable Sectors: Amerikon Sector - The Imperial battleship Merciless Death disappeared in this sector.Caligari Sector - The Caligari Sector is a vast, ancient and forgotten region on the fringes of the Segmentum Tempestus, filled with shadows that hide hundreds of tainted worlds. It is a sector plagued by the mysterious "Warpsurges," which are smaller, but highly unpredictable manifestations of the dreaded Warp Storms. Far from the guiding light of the Astronomican and torn apart by the foul tempests that can twist reality and cut off entire star systems for centuries, leaving them ripe for Chaos infestation, the Caligari Sector is a haven for the Heretic, the outlaw, the xenos and the corrupted.Caradryan Sector - Plagued by the proximity of the great Caradryan Warp rift which has recently entered a new cycle of heavy activity, this sector has increasingly been plagued by revolts, insurrections and other acts of mass-madness, forcing the Inquisition to call for a new Imperial Crusade to gather on the Shrine World of Ero.Coptis Sector - The planet Karis Cephalon, an Imperial world and the site of an astrological convergence lies in the Coptis Sector. The mutant slave labor trade in this sector was broken up by the Inquisitor Tyrus. "The Angel," an ancient weapon from the Dark Age of Technology, was hidden within the catacombs under the Amethyst Palace, the heart of Karis Cephalon's capital city, which is centered around the pre-Imperial construct known as the Needle of Sennamis (a possible psychic amplifier). The sector was resettled by the Imperium during the Great Crusade in the early 31st Millennium. The sector lies 5,300 light years from Terra.Chiros Sector - The Chiros Sector encompasses the border regions of both the Segmentum Tempestus and the Segmentum Pacificus. At the beginning of the 41st Millennium, this sector saw a rise in both xenos incursions and rebellious uprisings which made it a hotbed of Imperial military activity against Aeldari pirates, Orks and Renegades.Donorian Sector - This sector is home to several alien races, including the K'Nib and the Clawed Fiend. The Donorian Sector may also lie partly in the Segmentum Solar.Eurydice Sector - Founded following the Age of Apostasy in the 36th Millennium, the Eurydice Sector was born only after the famed Dark Marches Crusade had liberated its worlds from the multitude of xenos lifeforms that had dominated it for so long. Following the untimely demise of the Orpheus Sector, the Eurydice Sector has been constantly reinforced in order to form a bulwark against the emerging threat of the Necrons.Forsarr Sector - A long-established Sector Imperialis which contains the homeworld of the Raven Guard Chapter, Deliverance. Due to its proximity to the Ork Empire of Octavius, the Forsarr Sector has increasingly suffered from the violent Ork migrations known as WAAAGH!s.Haxan Sector - One of the four new sectors founded in M36 following the Dark Marches Crusade.Leyak Sector - One of the four new sectors founded in M36 following the Dark Marches Crusade. As of 976.M37 all contact with the Leyak Sector has been lost.Loki Sector - The planet of Rynn's World, an Agri-world that is also the homeworld of the Crimson Fists Chapter of Space Marines, lies in the Loki Sector. The Loki Sector has been the site of an ongoing Imperial war against the Orks of the Empire of Charadon. The greatest of their number was the Ork Warlord Snagrod the Arch-Arsonist, who led the Greenskin conquest of Rynn's World and is still at large in the sector.Orpheus Sector - The Orpheus Sector was a Sector Imperialis of the Segmentum Tempestus. This fortress realm had endured for nearly four thousand years against the ravages of the Ork and the predations of the Eldar. The destruction of civil war and the malevolence of Chaos, would yet prove to be as defenceless as a new-born before the horror of what was to come -- the Necron Maynarkh Dynasty. Awakened from their slumber, this malevolent and sinister Necrontyr dynasty was known for its savagery and malice. Emerging from their millennia-long stasis sleep, the Maynarkh pursued their unnatural lust for destruction and bloodshed. After years of probing and study, eventually this Necron dynasty first made contact with the Imperium in the Orpheus Sector, which resulted in the ongoing Orphean War. Despite the mobilisation of the sector's Imperial Navy Battlefleet Orpheus, multiple Imperial Guard regiments and local Planetary Defence Forces, it was still not enough to halt the xenos onslaught. Even with the help of multiple Space Marine Chapters, including the Minotaurs, Marauders, Nemesis Chapter, Red Seraphs and the Angels Revenant, was not enough to stem the Necron tide. By 995.M41, three years after the conflict began, the war had become unsustainable, with attrition losses reaching 60%. Segmentum Command believes the Orpheus Sector cannot be saved without a Crusade-level campaign, which would take the Imperium a minimum of thirty years to organise. Faced with such dire prospects, Imperial war savants and strategists believe the only viable option left is to enact Exterminatus.Spartus Sector - The planet Jericho III had its capital city destroyed by a Dark Eldar raid that resulted in the deaths of over 20,000 inhabitants and the hideous enslavement of countless others. The Dark Eldar next raided the Forge World of Stratix's polar arsenal, and stole experimental Imperial military hardware. The planet Vistro in the sector was the destination of an Imperial convoy that was also attacked by the Dark Eldar, who stole strategic ores from the Imperial freighters before destroying several of them outright.Uhulis Sector - The Uhulis Sector is an important Sector within the Segmentum Tempestus and mostly consist of overpopulated Hive Worlds and other stategically important worlds. Due to its proximity to the now lost Orpheus Sector, the Uhulis Sector contributed vastly in the colonization progress that began in the Haxan, Leyak, Eurydice and Orpheus Sectors in the wake of the Dark Marches Crusade. In the mid 32nd Millennium, the Sector was ravaged by the Ork populated Space Hulk known as "Da Iron Worm", leading to the loss of the Fortress World of Armstrong and Velgagrad, and perhaps more importantly the Forge World of Temaxia.Warre Sector