When Cardinal Duke Graventhorne feared Venerata’s mission was lost on Findhorn, he petitioned Terra to send another mission. Many years later, long after Venerata’s mission was rediscovered, the fleets of House D'Hautville arrived. With them came a new mission, an orders militant group dedicated to St. Mina.
These sisters were part of a penitence assigned to House D’Hautville who was charged with transporting them and sponsoring their settlement in the sector. The mission decided to forgo joining Venerata’s orders on Findhorn and set up on D’Hautville’s holding of Aurex. The official line was that they were to watch over the stray house of D’Hauteville. Yet, some allege that the real reason for not joining Venerata was due to the new mission’s unconventional interpretations of ecclesiarch faith, including their overt tolerance towards psykers.
As followers of St. Mina, these sisters grew into a full preceptory known as the Sisters of the Midnight Watch, a dual reference to St Mina’s dark and brooding demeanor and their vigilance in protecting Man from darkness. The Sisters of the Midnight Watch are known (and reviled) for their radical tendencies and as House D’Hauteville has become more established, the Midnight Watch has moved more towards an ally, rather than a shepherd. The Order has even made somewhat of an industry out of their tolerance for the psyker and run Imperial conditioning facilities that train psykers for use in the sector’s Imperial Guard. They’re unofficial mandate is to use and mold the psyker in the Emperor’s service rather than have the psyker turn against man.
Regardless of opinion, almost every Imperial Guard or Ministorium sanctioned psyker in Agrippa comes from the conditioning facilities of the Midnight Watch on Aurex.