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The Needful Maidens were nine San'Shyuum females who immigrated from Janjur Qom to High Charity in 850 BCE. They were brought over to the planetoid in hopes of restoring some genetic diversity to the population of the Prophets.
In 2200 BCE, a war broke out between the Stoics and the Reformists, two factions of San'Shyuum who held opposing views about what should be done with Forerunner relics. The Reformists, viewing technological advancement as the true answer, stole the Forerunner Dreadnought in 2100 BCE, taking with it a small fragment of their homeworld and all of the Reformists aboard. After this schism the two factions stayed apart for more than a thousand years.
Due to the small population of San'Shyuum aboard the Dreadnought, though, the Reformists quickly realized that their population could risk inbreeding. Numerous restrictions on breeding were thereby made, including the Roll of Celibates, in order to extend genetic diversity within their population. These measures helped but ultimately only slowed their eventual gene pool stagnation. The San'Shyuum of High Charity gradually grew weaker and less fit, hunching over, growing thinner, and making less effort to stand without the aid of antigravity belts and gravity thrones.
By 850 BCE, inbreeding had become enough of a problem that the Prophets decided to defy their self-imposed exile from Janjur Qom. A voyage was commissioned to return to their homeworld, to the Reskolah region, and take home native females who would become wives and mothers for High Charity's citizens. The initial plan for the mission involved abducting females, but after objections the plan was softened to only taking females who agreed to leave their homes.
Prior to the mission, the females were contacted in secret by an Eye's hologram, telling them of a new home they could travel to and what the time the Covenant would arrive. While some stayed away out of fear of the "aliens", nine San'Shyuum accepted and agreed to meet by the shores of their village Crellum. Each garbed themselves in a traditional fertility outfit and organized their own plan to be sure the visitors could be trusted. Eight of the females hid, riding aboard an ilpdor to protect themselves, while their leader Lilumna waited by the coast to meet with the strangers. At night she met Mken 'Scre'ah'ben and his escort, who had been sent to retrieve them and who she deemed trustworthy.When she signaled that it was safe, the others made their presence known and came along with the Covenant to travel to High Charity
However, the trip to High Charity went awry. When heading to the ship the group was attacked by a folasteed patrol, who had been alerted of the mission by several captured Covenant members. The party took some casualities, but all the Maidens made it aboard the ship Vengeful Vitality and into orbit. Once there the ship was attacked again, damaged by a Stoic missile. The females were moved from the corvette's hold to the crew's quarters for their safety, though one, Burenn, nearly died when she was caught in the hangar just before the hull decompressed. She was rescued at the expense of a Forerunner luminary, and the corvette escaped into slipspace shortly thereafter.
After arriving at High Charity the nine females were apprenticed to Mken's wife Cresanda to learn the customs of their new life. The Maidens experienced conflicted emotions about their immigration, sometimes homesickness for Janjur Qom, other times wonder at their new advanced home. They were a bit appalled by the physical degeneracy of Reformist males, but came to appreciate their politeness and courtesy, compared to the rougher and stronger men from their homeworld. The females eventually took on mates and sowed new genes, and became known as the "Needful Maidens" in retellings of the expedition in the following centuries.
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