Jesus3747 We originally came from another galaxy than teh current one, like in this place, the Cult has been attacked, and defended in return, when the attacks didn´t stop, the Cult dominated the factions that started the war, this went on until the whole galaxy was under control of the Cult, this way may not have been completely right, but it was the only way they knew to permanently stop the attacks on their borders.
There is enough "resources" back in the other galaxy to run the current fleet until the end of time, we came here to see what this galaxy is like, whoever wanted could join the Cult by their own will, but if this galaxy would prove entirely hostile (which is unlikely, since there is so many different factions) well...
The Cult originally did not plan on expanding it´s borders, leaving temples here for those that would like to join, eventually returning to the place of it´s origins and then, the war started, once again, as so many times before.