Castellan

"A castellan is a cavalier who dedicates himself to the defense of a castle or walled city. Though not as celebrated as the cavaliers who ride forth to take on distant foes, the castellan is no less brave or important, for the castellan and his allies are the last line of defense for those who depend on the fortification for protection."
-- Pathfinder Castellan (Cavalier Archetype)

Castellan is also the Elven word for Seneschal. House Shajara address their seneschal as Castellan, although it is unclear whether they are using it as a title or as a name.
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