From Halopedia, the Halo wiki
The Diplomatic Corps of the Unified Earth Government is the collective body of foreign diplomats accredited to it.
In the latter half of 2558, Melody Azikiwe, an envoy representing the diplomatic corps, was dispatched to the planet, Carrow, a world in a Joint Occupation Zone. She was tasked with forging a lasting peace between the humans and Sangheili present but also had been recruited by the Office of Naval Intelligence to assist in the rescue of the Spartan-IIs of Grey Team, held captive by a Sangheili fleetmaster.
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