Comes excubitorum

Excubitors
Active	ca. 460 – ca. 1081
Country	Byzantine Empire
Type	heavy cavalry, imperial guard
Garrison/HQ	Constantinople, Bithynia, Thrace
Commanders
Notable commanders	Justin I, Marcellus, Tiberius II, Maurice, Philippicus, Priscus, Nicetas, Valentinus, Michael II, Constantine Opos

This article is part of the series on the military of the Byzantine Empire, 330–1453 AD
Structural history
Byzantine army: East Roman army, Middle Byzantine army (themes • tagmata • Hetaireia), Komnenian-era army (pronoia), Palaiologan-era army (allagia) • Varangian Guard • Generals (Magister militum • Domestic of the Schools • Grand Domestic • Stratopedarches • Protostrator)
Byzantine navy: Greek fire • Dromon • Admirals (Droungarios of the Fleet • Megas doux)
Campaign history
Lists of wars, revolts and civil wars, and battles
Strategy and tactics
Tactics • Siege warfare • Military manuals • Fortifications (Walls of Constantinople)
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The Excubitors (Latin: excubitores or excubiti, literally "those out of bed", i.e. "sentinels"; transcribed into Greek as ἐξκουβίτορες or ἐξκούβιτοι) were founded in c. 460 as the imperial guards of the early Byzantine emperors. Their commanders soon acquired great influence and provided a series of emperors in the 6th century. The Excubitors fade from the record in the late 7th century, but in the mid-8th century, they were reformed into one of the elite tagmatic units, the professional core of the middle Byzantine army. The Excubitors are last attested in 1081.

The Excubitors were founded by Emperor Leo I (reigned 457–474) c. 460 and numbered 300 men, often recruited from among the sturdy and warlike Isaurians, as part of Leo's effort to counterbalance the influence of the magister militum Aspar and the large Germanic element in the East Roman army. Unlike the older palace regiments of the Scholae Palatinae, which were under the control of the magister officiorum and eventually degenerated to parade-ground formations, the Excubitors long remained a crack fighting force. In addition, while the Scholae were garrisoned throughout Thrace and Bithynia, the Excubitors were billeted in the imperial palace itself and formed practically the only garrison of Constantinople in the 6th century. Their high status is further illustrated by the fact that both officers and ordinary Excubitors were often sent for special missions by the emperors, including diplomatic assignments.

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