Achilus Crusade - The Warp Gate: The catalyst for the launching of the Achilus Crusade was the unexpected discovery of an active Warp Gate in the turbulent margins of the Halos Stars close to the border of the Calixis Sector in the Segmentum Obscurus.This ancient and vastly cyclopean alien device of unknown age proved to be both active and stable, with a corresponding gate-aperture into realspace on the other side of the galactic core at the edge of the Jericho Reach.Though the Jericho Reach had at one time been under Imperial control, the existence of this gate within its boundaries had never been discovered; a further mystery that has never been solved. The Warp Gate and the possibilities it offered only came to light in 755.M41, when the Navigator of the Imperial flag-frigate Spear of Tarsus sensed something causing a localised area of calm in the great Warp Storm border through which she was steering passage.Dropping out of the Warp close to the source of this tranquil sea, the frigate found itself in the presence of a vast Warp Gate of xenos design, placed in the cold blackness of interstellar space far from the orbit of any star; a gate that, though undoubtedly ancient, had been activated (or re-activated at any rate) in the recent past.With this discovery, a chain of events were set in motion that would cause the Achilus Cursade to be launched across the stars.Once the Spear of Tarsus had returned to Imperial space bearing news of its discovery, it was not long until a secret expedition was launched to discover the nature of the gate and where it led. Ships serving the Adeptus Mechanicus Explorators and the Ordo Xenos sent scouting ships through, crewed with their most able agents and experienced Navigators.Their swift return not only told of another gate, also hanging in the empty void far from any star, but also of the certain truth that this other gate lay in the Eastern Fringe of the Segmentum Ultima, near the Jericho Reach all the way on the other side of the galaxy.With this realisation, a plan was born within the minds of the great lords of the Imperium: the possibility of using the gate to launch a crusade into the Jericho Reach and reclaim it for the Imperium as a stepping stone to other conquests. The idea found favour with the High Lords of Terra, who gave it their blessing, and so the idea of a most singular crusade grew in possibility in the minds of the great until Lord Militant Tiber Achilus was given mandate to make it a reality.The High Lords were mindful, however, that the existence of the gate and what it portended offered dire peril as well as possibility, and decreed that the crusade was to be launched from a staging point far from the territory it intended to conquer under a shroud of deepest secrecy.But, like so many other great campaigns launched in the millennia that the Imperium has stood, it was intended to bring swift victory and to use the light of the God-Emperor to drive back the darkness.On the eave of the Feast of the Emperor's Ascension in 777.M41, countless millions of Astra Militarum, thousands of Adepta Sororitas, and as many as a dozen Space Marine Chapters advanced to conquer the worlds of the Jericho Reach in the shadow of Battle Titans and to the thunder of the guns of the Imperial Navy. It was a bold and fiery beginning.