Pentakosiarch

Pentakosiarch (Greek: πεντακοσιάρχης, pentakosiarches in Modern Greek usually πεντακοσίαρχος, pentakosiarchos), meaning "commander of 500", is a Greek military rank, first adopted in the infantry of the Army of Macedon (cf. Aelianus Tacticus and Plutarch, Life of Alexander, 76). The pentakosiarch commanded a pentakosiarchy (πεντακοσιαρχία, or pentakosiarchia) of 512 men, composed of two of 256. Two pentakosiarchies in turn formed a chiliarchy and were commanded by a chiliarch.

The rank was revived for the irregular forces of the Greek rebels during the Greek War of Independence (1821–1829).

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