From Halopedia, the Halo wiki
A Seneschal is an honorable position among the noble houses of the Sangheili, likely involved in the stewardship of domestic affairs. During the time of the Sangheili's membership in the Covenant, those warriors serving in the role of the Evocati were expected to take up a number of other roles after some period of service, one possibility being that of a seneschal. Little else is known of the Seneschals, aside from their relation to the Evocati. Nevertheless, in the postwar period a number of documents have been recovered providing more insight on the role's purvew.
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