古代斯巴达设有五督政官（ὁράω，「监管」的意思），每年由全体城邦公民选出。这五人负责协助两个国王执政，他们每月都要立誓効忠国王，国王则立誓効忠法律。据说前7世纪的来古格士（Λυκοῦργος，或译赖库尔戈斯）首先设立五长官，在他出外行军时替他打理朝政。

The ephors were leaders of ancient Sparta and shared power with the two Spartan kings. The ephors were a council of five elected annually who "swore on behalf of the city", while the kings swore for themselves.

Herodotus claimed that the institution was created by Lycurgus, while Plutarch considers it a later institution. It may have arisen from the need for governors while the kings were leading armies in battle. The ephors were elected by the popular assembly, and all citizens were eligible for election. They were forbidden to be reelected. They provided a balance for the two kings, who rarely cooperated with each other. Plato called them tyrants who ran Sparta as despots, while the kings were little more than generals. Up to two ephors would accompany a king on extended military campaigns as a sign of control, even gaining the ability to declare war at some points in Spartan history.