An epistates (Greek: ἐπιστάτης; plural ἐπιστάται, epistatai) in ancient Greece was any sort of superintendent or overseer.
In the Hellenistic kingdoms generally, an epistates is always connected with a subject district (a regional assembly), where the epistates, as resident representative of the king, exercised control and collected taxes.
The phalanx was made up of alternate ranks of protostates and epistates.
The word might be better understood as belonging to the set of Greek words meaning 'visitor' or 'divine visitation' (episkope), 'letter of instruction' (epistole), as well as 'guardian' or 'caretaker' (episkopos), which was a word later translated as bishop.
This article about the Ancient Greek language is a stub.