Sacristan - The Great Crusade: It was not until the glorious years of the Great Crusade in the late 30th Millennia that contact was reestablished with the surviving Knight Worlds. When the first Rogue Traders discovered one of these scattered enclaves, they quickly recognised the potential in the towering fighting machines and the robust society that supported them. Upon returning their findings to the nascent Imperium of Man, the Rogue Traders strongly recommended that these Knights be returned to the Imperial fold, for their value as a military asset could not be overstated. Further, it was asserted that where one Knight World had survived though the darkness of Old Knight, surely more must have done the same. They should be sought out and returned to the bosom of their race so that they might aid in the furtherance of the Imperial Truth. Not only were the Knight suits incredibly potent weapons of war, but their planets of origin were still rich in resources. Perhaps most important of all, these were worlds still rich with the marvels of the Age of Technology. Though many devices had been forgotten, abandoned or destroyed as the years passed by, still the Knight Worlds were treasure troves of archeotech and mechanical wonders. For this reason, it was the Mechanicum who strove the hardest to seize the Knight Worlds for their own.As the Great Crusade rolled out across the galaxy, the Mechanicum established hundreds of new Forge Worlds. Many were built amid the ruins of past glories, worlds once rich in the iron bounty of progress. Others were hewn from unsettled worlds found to be well positioned or heavy with natural resources. Yet regardless of the Mechanicum's stated reasons, it seemed that a surprisingly high number of their newly founded centres of power lay close to one or more surviving Knight Worlds. Each time this happy coincidence occurred, the Forge Worlds' senior Magi wasted no time in dispatching missionaries to aid these long-abandoned enclaves of humanity. In return for the ruling Nobles' pledge of military aid, the Mechanicum offered the word of the Omnissiah, and the ancient knowledge that came with it. The artisan castes of the Knight Worlds had done what they could to stave off the rigours of time, yet precious few of the Nobles' Knight suits still operated at anything close to optimum efficiency, and many had ceased to function at all. By inducting the craftsmen and armourers into the mysteries of the Cult Mechanicus, the Mechanicum could provide the Knight Worlds with the ability to regain their former glory.While few refused the Tech-priests' gift of knowledge, most did not give themselves over completely to the Omnissiah, instead retaining their own independence and swearing their allegiance to the Emperor instead. As for the Knight Worlds that wholly accepted the aid of the Martian Priesthood and the word of the Omnissiah, their Nobles had given away much of their autonomy and freedom. Vows of allegiance now obligated the Nobles to lend military aid to the Mechanicum whenever it was demanded. More insidious, however, was the change that had occurred in their artisan classes. The craftsmen who saw to the well-being of the Knight suits endured indoctrination and reeducation at the hands of the Tech-priests. Most submitted willingly to this decade-long process, for the end result would be unsurpassed skill in the trade that they and their forebears had practiced for generations. As the Mechanicum inducted these craftsmen and artisans into their deeper mysteries, so they renamed them Sacristans and indoctrinated them into the Cult Mechanicus. The Sacristans returned to their worlds offering unequivocal service, yet their allegiance was now to the Mechanicum, body and soul.As the years passed by, the Sacristans established themselves as a religious brotherhood, an order of half-remembered mysteries and veiled secrets. Gradually they began to speak with one voice, soon coming to wield significant political power through the threat of withholding their knowledge and expertise. This did not work on every Knight World, for the Sacristans were still technically the Nobles' legal vassals, and on some worlds weight of tradition or force of personality cowed the Sacristans into subservience. However, this was the exception rather than the rule. In general, this has benefited the knightly houses, for the Sacristans act as something of a counterpoint to the natural arrogance and warlike tendencies of the Knights, and have often been able to arbitrate between different houses to ensure they do not wipe one another out in bitter feuds. While other organs of the Imperium had blustered, bribed or bullied in an attempt to win the Knight Worlds to their cause, the Mechanicum had performed a slow and silent invasion that had left the Knight Worlds dependent upon them for their continued existence. Even so, the Mechanicum had not counted upon the fierce independence inherent in the Knight Worlds' nobility. So it was that while many Knight Houses would become beholden to the Mechanicum many more would still choose to stand apart.