Taxiarchos

Taxiarch, the anglicized form of taxiarchos or taxiarchēs (Greek: ταξίαρχος or ταξιάρχης) is used in the Greek language to mean "brigadier". The term derives from táxis, "order", in military context "an ordered formation". In turn, the rank has given rise to the Greek term for brigade, taxiarchia. In Greek Orthodox Church usage, the term is also applied to the Archangels Michael and Gabriel, as leaders of the heavenly host, and several locations in Greece are named after them.

In Ancient Greece the title/rank was held by a number of officers in the armies of several but not all city-states, with Sparta being a notable exception. In Classical Athens, there were ten taxiarchs, one for each of the city's tribes (phylai), a subordinate to the respective strategos. The perhaps most famous taxiarchs however were those of the ancient Macedonian Pezhetairoi infantry.

The term first appears in use in the Byzantine army in the late 6th-century Strategikon of emperor Maurice, where it is reserved for the commander of the elite Optimatoi mercenary corps. In the 10th-century, the term was revived and refers to the commander of one of the new type of infantry brigade (taxiarchia), composed of 500 heavy infantry, 300 archers and 200 light infantry. On account of their numerical size, these units were also known as chiliarchia, and their commander correspondingly as chiliarchos, and are also equated to the thematic droungos under a droungarios. During the 11th century, with the demise of the thematic armies, the rank rose in importance, and eventually surpassed and replaced that of tourmarches, so that in the Komnenian-era army, the taxiarchia was the largest-scale permanent infantry formation.

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