Excubitors

The Excubitors (excubitores or excubiti, literally "those out of bed", i.e. "sentinels"; Greek: ἐξκουβίτορες or ἐξκούβιτοι) were founded in circa 460 AD 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 AD.

History
The Excubitors were founded in Late Antiquity by Emperor Leo I (reigned 457–474) circa 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. Unlike the Scholae, which 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, including diplomatic assignments.



The unit was headed by the Count of the Excubitors (comes excubitorum; κόμης τῶν ἐξκουβίτων/ἐξκουβιτόρων, komēs tōn exkoubitōn/exkoubitorōn), who, by virtue of his proximity to the emperor, became an official of great importance in the 6th and 7th centuries. This post, which can be traced up to circa 680, was usually held by close members of the imperial family, often virtual heirs apparent. Thus it was the support of his men that secured Justin I (r. 518–527), who held the post at the time of the death of Anastasius I, his elevation to the throne. Similarly, Justin II (r. 565–578) relied on the support of the Excubitors for his unchallenged accession; their count, Tiberius, was a close friend who had been appointed to the post through Justin's intervention. Tiberius was to be the Emperor's right-hand man throughout his reign, eventually succeeding him as Tiberius II (r. 578–582). He too would be succeeded by his own comes excubitorum, Maurice (r. 582–602). Under Maurice, the post was held by his brother-in-law Philippicus, and under Phocas (r. 602–610) by Priscus. The power that went with the post, and the intrigues of men like Priscus and, in the early 640s, the would-be usurper Valentinus, doomed the post to emasculation and eventual eclipse during the latter half of the 7th century.

After a lapse towards the end of the 7th century and the first half of the 8th century, the Excubitors reappear in historical sources, under a new commander, the Domestic of the Excubitors (δομέστικος τῶν ἐξκουβίτων/ἐξκουβιτόρων, domestikos tōn exkoubitōn/exkoubitorōn) and in a new capacity, as one of the imperial tagmata, the elite professional central army established by Constantine V (r. 741–775). As one of the tagmata, the Excubitors were no longer a palace guard, but a unit actively engaged in military campaigns. At the same time, they were created as a counterbalance to the thematic armies and constituted a powerful tool in implementing the iconoclastic policies pursued by Constantine V; their allegiance was so strong that pro-iconodule regent Irene had to forcibly disarm them in 786.



The Domestics were originally of strikingly low court rank (mere spatharioi), but they gradually rose to importance: while in the Taktikon Uspensky of circa 842 the Domestic of the Excubitors ranks behind all the thematic stratēgoi, in the Klētorologion of 899, the Domestic is shown as superior to the stratēgoi of the European themes and even to the Eparch of Constantinople. At the same time, their rank rose to that of prōtospatharios and even patrikios. The most prominent Domestic of the Excubitors of the period was Michael II the Amorian (r. 820–829), whose supporters overthrew Emperor Leo V the Armenian (r. 813–820) and raised him to the throne. In the latter half of the 10th century, probably under Romanos II (r. 959–963), the regiment, like the senior tagma of the Scholae, was split in two units, one for the West and one for the East, each headed by a respective Domestic.

As with most of the tagmata, the regiment did not survive the great upheavals of the later 11th century, when foreign invasion and constant civil wars destroyed much of the Byzantine army. The last mention of the Excubitors occurs in Anna Komnene's Alexiad, where they are recorded for the last time as participating at the Battle of Dyrrhachium in 1081 under Constantine Opos.

Structure
The internal structure of the original excubitores regiment is unknown. It is known that it was a cavalry unit and that it had officers called scribones. The historian Warren Treadgold speculates that they fulfilled a role similar to the regular cavalry decurions, commanding troops of 30 men each, but John B. Bury suggested that the scribones, though associated with the excubitores, remained a separate corps.

In its later incarnation as a tagma, the regiment (often called collectively τὸ ἐξκούβιτον or τὰ ἐξκούβιτα) was structured along standardized lines followed by the other tagmata, with a few variations. The domestikos was assisted by a topotērētēs (Greek: τοποτηρητής, lit. "placeholder", "lieutenant") and a chartoularios (Greek: χαρτουλάριος, "secretary"). The regiment itself was divided into at least eighteen banda, probably each commanded by a skribōn (Greek: σκρίβων). Each of them was further divided into sub-units headed by a drakonarios (Greek: δρακονάριος, deriving from the late Roman draconarius), and included three classes of standard-bearers who functioned as junior officers: the skeuophoroi (Greek: σκευοφόροι, "standard carriers"), signophoroi (Greek: σιγνοφόροι, i.e. signifers) and sinatores (Greek: σινάτορες, from the late Roman rank of senator). There were also the usual messengers (Greek: μανδάτορες, mandatores) under a prōtomandatōr, some of whom were also termed legatarioi (Greek: λεγατάριοι).

The size of the tagma of the Excubitors and its subdivisions can not be determined with certainty; as with the other tagmata, scholars are of differing opinions regarding its numerical strength. Drawing on the lists of officers and accounts of Arab geographers Ibn Khurdādhbah and Qudāmah, historian Warren Treadgold maintains an establishment strength of circa 4,000 men, which for the Scholae and the Excubitors rose to circa 6,000 with the division of the regiments in the mid-10th century. Other scholars, most prominently John Haldon, have revised estimates to some 1,000 men for each tagma.