From Halopedia, the Halo wiki
Sometime before 2552, as the state of the Refuge had begun to deteriorate, some Sangheili believed that an apocalypse was inevitable. Insa 'Greftus believed that the "Forgotten Gods" channeled themselves physically through him and they wanted the Sangheili to depart the Refuge. The Forgotten Gods had allegedly told 'Greftus the location of Sanghelios, and they wanted the Sangheili to use the colony's ancient starships to return to the planet. 'Greftus initiated a rebellion in Section Five of the Refuge, and he established the "Way of 'Greftus" and the 'Greftus Faction. Declaring that 'Greftus' claims were ramblings caused by Blood Sickness, Kaidon N'Zursa 'Xellus sent guards for 'Greftus. The rebel was ejected out of the Refuge via airlock into space for his "Failure of Clan Integrity". All Ussans in the Refuge witnessed 'Greftus' death.
Although 'Greftus died, his faction survived. Years after his execution, it was revived by a Blood Sick Sangheili who called himself 'Kinsa. 'Kinsa claimed to be the voice of 'Greftus and initiated another rebellion on the colony. Taking over several sections of the Refuge, 'Kinsa forced the residents to worship 'Greftus and himself. The rebellion was eventually quelled and the faction dissolved due to the arrival of several Sangheili from the Covenant and the repair of monitor Enduring Bias.
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