Emperor of Mankind - Imperial Webway Project: Approximately two standard centuries into the Great Crusade, the Emperor decided to return to Terra to oversee a special project that He intended to cap His ambitions for Humanity. This was the secret Webway Project, in which the Emperor planned to employ the assistance of a special artefact from the Dark Age of Technology -- the Golden Throne -- that had been discovered on Terra beneath a huge and inhospitable desert on the continent of Asia.The Emperor planned to use the Golden Throne to enter and reshape the labyrinthine dimension of the Aeldari Webway to serve as a direct and instantaneous transport network between all the worlds of the Imperium. This Human portion of the Webway would recreate the vast network of Warp Gates that had once bound together the Old Ones' and the Aeldari's ancient interstellar empires and would allow Humanity to advance at a more rapid rate, scientifically and economically, than at any other time in its history.The Webway was a far more efficient means of travel, and most importantly bypassed the depredations of Chaos within the Warp that represented a constant hazard of death or spiritual corruption to Human faster-than-light space travel. The ultimate objective of the Webway Project was for the Emperor to completely sever Humanity from the need for the Warp in its entirety. This would further deprive Chaos of its power to corrupt and destroy and weaken the psychic emanations that powered and sustained the Chaos Gods through the protective psychic wards that shrouded every Webway corridor.All these benefits would come as the Emperor guided His species within the protective embrace of the Webway in its evolution into a fully psychic race. This would assure its ascendancy on the galactic stage beyond what even the lost Aeldari Empire had once managed to achieve and unleash a golden age of Human civilisation unlike any before known.A Human-dominated Webway would also truly unite the Imperium, preventing Mankind from ever again being divided by time and great distance. But this project would require all of the Emperor's considerable attention and had to be pursued in secret, lest the Aeldari or other opponents of the project learn of it and seek to stop it before His efforts could come to fruition.The Golden Throne had been built during the Dark Age of Technology to allow Human access to the Webway and took the form of a heavily mechanised throne created from an unknown type of psychically-reactive, gold-complected alloy that was suspended over a pair of massive doors composed of the same golden alloy. These doors acted as the portal to the Webway and were supposedly large enough for a Warhound-class Scout Titan to walk through upright.The Golden Throne was originally located in the subterranean depths of the Imperial Palace where the Emperor's gene-laboratory complex had once stood, an area known as the "Imperial Dungeon." Hundreds of red-robed Mechanicum Tech-priests and servitors toiled in the Imperial Dungeon, as the Emperor sat upon the Golden Throne and used His immense psychic powers to hold the portal into the Webway open for His workers, who constructed a new section of the labyrinth dimension intended to connect Terra to the rest of the largely abandoned transdimensional transport network.Because the Webway had been constructed from a psychically-resistant material intended to protect it from penetration by the entities of the Warp, and Humanity did not possess the technology required to replicate it, the Emperor had to personally shield the new Human-built sections of the Webway from Warp incursions. This required him to remain on the Golden Throne continuously and was the reason why He had been forced to leave the Great Crusade in the hands of His primarchs and return to Terra to oversee the project personally.As such, following the extraordinary victory of Imperial forces over the greatest Ork WAAAGH! encountered by the Imperium to that time during the Ullanor Crusade, the Emperor decided that He was no longer directly needed to command the efforts of the Great Crusade. To this end, the Emperor placed Horus, His favoured and most talented son, in charge of the military advancement of the Great Crusade in His stead.Horus was foremost amongst the primarchs and was the first re-discovered by the Emperor on the dying world of Cthonia that lay so close to Terra that Warp-Drive was not needed to reach the planet. Horus was the only primarch to serve in the Great Crusade alongside his father for many solar decades and was the most highly honoured of the Emperor's sons, the primarch he most trusted and most loved.The two had fought together at the forefront of the early Great Crusade. The Emperor had protected Horus during the Siege of Reillis while Horus repaid the favor during the Battle of Gorro. During the Battle of Gyros-Thravian, the Emperor slew the mighty Ork Warboss Gharkul Blackfang after it had held off three of his primarchs.With such a history between them, the Emperor felt Horus was the man to lead the Great Crusade in His absence. Granting Horus the unique title and rank of Warmaster, the Emperor declared that the time had come for His sons to show Him what great leaders they were. Turning His back on direct military matters, the Emperor created the Council of Terra (the precursor of the Senatorum Imperialis), the Imperial Tithe, and expanded the civil governing and bureaucratic bodies of the Imperium like the Adeptus Administratum, before retiring in seclusion beneath the Imperial Palace to begin work upon the Golden Throne and the Webway Project.But the Emperor's decision to not tell His sons why He had retired to Terra as well as His decision to begin shifting the Imperium's government out of the direct control of the primarchs on the War Council and to the Terran nobility and bureaucrats whom they detested sowed the seeds of discord among the primarchs. So, too, did disquiet over the Emperor's decision to raise Horus above his brothers by naming him the Warmaster and thus their commanding officer.From these seeds of ambition, pride and jealousy the Chaos Gods would find fertile ground to corrupt many of the primarchs and bring on the horrors of the Horus Heresy.