From Halopedia, the Halo wiki
In March 2553, Jul 'Mdama teleported to Hesduros from ONI Research Facility Trevelyan, landing in the middle of the "holy gate", surprising Panom's nephew Rdolo, who went to inform Panom. Panom informed Jul that while they sent soldiers to fight in the Human-Covenant War, they hadn't had any contact for over a year. Jul informed them of the Great Schism, the end of the war, the Arbiter's alliance with humans, and the start of the Blooding Years.
Jul also explained what he had learned about the Didact, who was known in local legends as a "holy warrior" who would come to the aid of the faithful in times of need. Being highly religious like the other inhabitants of his world, Panom soon became to view 'Mdama as a messenger with a divine purpose. He vowed to aid 'Mdama as he began a quest of vengeance against humanity, intending to gather forces and go to Requiem.
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