What's the noun for ephor? Here's the word you're looking for.
ephor
(historical) One of the five annually-elected senior magistrates in various Dorian states, especially in ancient Sparta, where they oversaw the actions of Spartan kings.
“The allegedly post-Lycurgan ephorate was abolished, the gerousia made subject to annual re-election, the dyarchy transformed into a de facto monarchy.”
“The team of archaeologists is from Britain's University of Nottingham and Greece's Ephorate of Underwater Antiquities of the Ministry of Culture.”
“The 24th Ephorate of Prehistoric and Classical Antiquities of the Greek Ministry of Culture excavated two cemeteries in Ierapetra, Crete, Greece.”