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Ambassador to Sanghelios
Rear Admiral Horatio Temkin is the UNSC ambassador to Sanghelios, represented primarily by Arbiter Thel 'Vadam's Swords of Sanghelios.
In 2558, Temkin organized the peace talks on Ealen IV. Captain Daniel Clayton, who served under Admiral Temkin, leaked the location of the negotiations to Covenant mercenaries who then proceeded to attack and halt the negotiations.