Being the junior of the twin orders, the uninformed often assume the Sisters of Victory, as they are often called, to take a purely subordinate role, but while they do make up many of the administrators of the orders, nothing could in fact be further from the truth.
Sisters make up the officer corps for carriers and cruisers, as well as the rest of the ship’s crew (aside from interceptor pilots) for carriers. They make up half of the Joint Oversight Commission–the day-to-day operations management of both orders, beneath the council of Mother Superiors and the Knights’ Grand Master–and even more of the Pontifical Council for Interstellar Justice-keeping, the meeting place between the two most famous Catholic orders and the pope. Finally, they are the primary order for intelligence-gathering and record-keeping (meaning that the delegations to oversee or negotiate with other powers are mostly sisters.) The Sisters’ espionage service (the Commission for Truth-Finding) have far-reaching agents, though the Knights, being the more technical and financially secure of the two orders, are often the source of tools and funding for those agents.
The Sisters of Victory work together with the Knights, and have since their inception in Year 173 SSC (Standard Solarian Calendar.) They were founded by St. Francesca Sofia Belmonte, in response to a perceived need within the Knights for intermediaries and administrators. Over the twenty years that she oversaw the order she founded, St. Francesca Belmonte, she brought them from that humble beginning to an order much resembling what it would later become, though it would not begin crewing warships with Sisters until the Year of Tumult (Year 218 SSC; the year the Horde began conquering human planets and the founding year of the Empire of the Stars.)
Since then, there have been constant little problems between the two religious orders, and eventually there was even a time when they tried to disentangle from each other. That was a time of five years in which the budding powers of the Federation and the Empire grew fat through conquest, and in which several proto-empires began, only to fall apart once the two orders were again at peace with one another and working together.
Due to human concupiscence there are regularly sisters (just as there are with knights) who violate their vows, and consequently are punished, with the most severe punishment being expulsion from their order. The Sisters, like the Knights, have idealistic pillars to which they are sworn; for them, they are: faith, hope, justice, and courage. In addition, like the Knights, they are sworn to obedience to the pope, the order, legitimate authorities, and their superiors, as well as to chastity.
Unlike the Knights, the Sisters do not take a vow of poverty, meaning that they are often known to involve themselves in commerce to a degree that the Knights do not. Because of this, the Sisters set up an Interstellar Arbitration Commission staffed by senior sisters and a scattered few men from among the Knights (who usually act as arbiters in cases involving sisters.)
The one area of the orders’ work in which the Sisters are largely absent is in the evangelization work. By long tradition, the Knights are the primary evangelizing order, both among humans and alien species. No one knows precisely why this tradition started–and many of the Sisters are irritated by it–but it still remains.
The Sisters of Our Lady of Victory are the junior order, but in spite of the misconceptions about them they (if anything) have the wider mission.
Interesting fact: Because the Sisters operate many choirs, orchestras, bands, and singing groups in their scarce free time, they are sometimes known as “the Singing Ladies” among spacers, though this has not caught on among the wide majority of peoples.