Keepers of the Dawn
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The Keepers of the Dawn was the name of a governing body that held considerable power over the San'Shyuum Reformists, and its members were the first San'Shyuum to be referred to as "Prophets." Centralized within the Forerunner Dreadnought during the War of Beginnings, the Keepers of the Dawn were led by the San'Shyuum known as Pervading Stone until his assassination at the hands of Breaking Shadow, a fellow member of this body.
War of Beginnings
During the War of Beginnings, the Keepers of the Dawn were one of the most powerful bodies within the Reformists' government, with Pervading Stone serving as their leader. Stone's father had been killed during the ground siege at Ulgethon, the first major battle in the San'Shyuum's conflict with the Sangheili. Driven by revenge, Pervading Stone spent years leading the Reformists as they laid waste to Sangheili colonies and outposts. Even after the harrowing events at Codisfold, he continued his brutal campaign to completely annihilate the enemy. He was known to silence and even eliminate dissenters, a group which began to grow in number following the revelation that the San'Shyuum were indeed still vulnerable aboard their keyship. After Breaking Shadow and Ushering Dusk—both fellow members of the Keepers of the Dawn—began to voice opposition to Stone's actions, he secretly ordered the assassination of Ushering Dusk. Dissent among the San'Shyuum grew even more when it was discovered that the Sangheili had begun to use Forerunner weapons against them. Still, Pervading Stone refused to entertain the possibility of peace with the Sangheili.
Eventually, after the location of Sanghelios had been discovered, Pervading Stone brashly took the Dreadnought to the Sangheili homeworld, intending to sever the head of their enemy once and for all. However, after some time of enduring the vessel's attacks on Sanghelios and its two moons, Qikost and Suban, the Sangheili responded by turning their warships armed with Forerunner-derived weaponry against the Dreadnought, shooting it down on Suban. There, it was held in place with gravity anchors, effectively trapping the San'Shyuum—including the Keepers of the Dawn—inside. The Sangheili proceeded to storm the ship, debating whether to simply destroy it and its inhabitants outright or breach the vessel and take it for themselves.
By 855 BCE, Pervading Stone's refusal to pursue peace with the Sangheili led to Breaking Shadow initiating a violent coup, ending with Stone's assassination. Acting as the Reformists' new leader, Breaking Shadow began working toward peace with the Sangheili. In 852 BCE, he sent an unarmed delegation to their enemies to recount what had happened over the last several years. Breaking Shadow and First Kaidon Pelahsar the Strident forged a tenuous alliance, forgiving the other's species for their past crimes. This was soon formalized in the Writ of Union, the founding document of the Covenant. It is unknown if the Keepers of the Dawn dissolved following these events, or if this governing body simply took on a new form.