Collegia Titanica - Treaty of Mars and the Great Crusade: Perhaps inevitably, there followed a period of outright war as rival sects of Tech-priests sought supremacy, whether doctrinal or temporal, but at length, an uneasy balance of power was achieved, although schisms, heresies and betrayals remained constant.An internecine web of power, patronage and influence came to bind the warring Mechanicum factions together, until eventually the Tech-priests of Mars were sufficiently united in purpose to expand their power beyond the Red Planet, beyond the Sol System, and out into a galaxy still riven by Warp Storms and preyed upon by monstrous Human tyrants and xenos fiends.No archive recalls the details of every Mechanicum colonisation ark sent forth into the darkness, but it is likely that their failure rate was astronomically high and that millions of Tech-priests and Martian colonists perished during this so-called "Long March." Nonetheless, some colony vessels did reach their target worlds through the Warp by luck or other circumstance and thus were the seeds of the Cult Mechanicus scattered across the galaxy.Some of these colony worlds would at length grow to become true "Forge Worlds," akin to Mars and yet in many cases possessed of their own variation of culture and cult ritual shaped by their own unique historical and environmental realities. Others became more of the so-called "Knight Worlds," colonies established on planets that were rich in resources and which would one day feed and sustain the ravenous appetites for food and resources of the Forge Worlds themselves.In time, the great Warp Storms which had divided the galaxy were dispelled as the 30th Millennium dawned after the Fall of the Aeldari and the birth of the Chaos God Slaanesh. At last, the rebirth of Humanity could begin. The powerfully psychic being known only as "the Emperor" led His followers against the tyrants of Old Night and during the subsequent Unification Wars finally united all the peoples of Old Earth -- now called Terra -- under one government for the first time in five standard millennia.Some say that the Tech-priests of Mars had long observed the scattered techno-barbarian tribes of Old Earth, watching them from afar as this great warlord arose from the multitudes of the techno-savages to unite those who would heed His message, and conquer those who would not. As He gained in power, the Tech-priests grew jealous of this distantly-observed individual and the mastery of technology He, above all the other petty warlords of Terra, so obviously possessed. And as His armies and His power grew, they knew that their irregular sorties to recover lost technological wonders from the ruins of Old Earth had come to an end.A genius the likes of which Mankind had never witnessed, the Emperor created the transhuman Space Marines of the Legiones Astartes and set above them His superhuman gene-sons -- the primarchs -- who would lead Humanity into a long-planned-for age of reconquest that would become known as the "Great Crusade."It was upon the slopes of the greatest mountain on Mars, Olympus Mons, that this man, if such a label could truly be applied to Him, the Emperor of Mankind, first set foot upon the Red Planet. Mars was the first Human colony He had encountered beyond Mankind's homeworld. Heralded by all those on Mars who met Him as the Omnissiah, the physical incarnation of the Machine God, some within the Cult Mechanicus were not entirely pleased with this turn of events. A few of these malcontents incited a short and bloody insurrection against the majority of those within the cult who called for an alliance with the Emperor, but eventually the opposition was crushed and Mars and Terra were finally reunited after millennia of separate development by the agreement called the Treaty of Mars in the late 30th Millennium.This accord formally founded the Imperium of Man as an alliance between Terra and the ancient Mechanicum government of Mars, and granted the latter the autonomy required to maintain their faith even as the Emperor intended to spread His secular and atheistic Imperial Truth across the galaxy. Upon Olympus Mons the lords of the Red Planet ascended to their place alongside the Imperium of Man, but the Mechanicum would ever remain an empire within an empire, for machine domains other than Mars existed across the galaxy and would in time swear fealty to the fabricator-general of Mars.In recognition of the fact that the Unification of all Humanity could not be achieved without the technological and scientific aid of the Mechanicum, Mars became an ally to Terra rather than her subject. With the massive Human resources of Terra and the colossal technical and industrial power of Mars, the Emperor could begin His mighty enterprise of reconquering the galaxy on a firm foundation. Many long-forgotten Human-settled planets were liberated and many more worlds were settled anew. Thus began the Great Crusade, and over the next 200 Terran years the Imperium of Man rapidly expanded across the galaxy.As the Emperor's hosts pushed ever outwards into the galaxy, casting back the horrors that had gripped the scattered Human worlds for so many long centuries, the Titan Legions marched with them. Fighting alongside the transhuman Space Marines of the Legiones Astartes, the elite void-soldiers of the Solar Auxilia and numerous other forces in the rapidly expanding Excertus Imperialis, the Titan Orders came upon other planets dominated by their long-lost kin, Forge Worlds not unlike Mars and ruled by similar techno-theocracies dedicated to the Machine God who had settled these worlds after being sent out by Mars into the interstellar void during Old Night.A few refused to acknowledge the primacy of the Red Planet over their variants of the Cult Mechanicus and had to be forced to submit, or in some cases were even destroyed. The majority however knew of the Red Planet through the few fragments of archive data and echoes of legend which had managed to survive after the settlement of their worlds during the Age of Strife, and willingly took their place in the new order.