Excubitors
The Excubitors were founded in as an imperial guard-unit by the Byzantine emperor Leo I the Thracian. The 300-strong force, originally recruited from among the warlike mountain tribe of the Isaurians, replaced the older Scholae Palatinae as the main imperial bodyguards. The Excubitors remained an active military unit for the next two centuries, although, as imperial bodyguards, they did not often go on campaign. Their commander, the Count of the Excubitors, soon acquired great influence. Justin I was able to use this position to rise to the throne in 518, and thereafter the Counts of the Excubitors were among the main political power-holders of their day; two more, Tiberius II Constantine and Maurice, rose to become emperors in the late 6th century.
In the later part of the 7th century the Excubitors appear to have morphed into a parade-ground formation, and they fade from the record as a corps. Individual seals of office suggest that the title of excubitor became an honorific dignity rather than an active military appointment during the early part of the 8th century. This changed, when the Emperor Constantine V reformed the corps into one of the élite - professional heavy-cavalry regiments that constituted the core of the Byzantine army of the middle-Byzantine period. Notable members of the regiment during this time include Saint Joannicius the Great, and Emperor Michael II the Amorian, who served as regimental commander, or Domestic of the Excubitors, before rising to the throne in 820. The Excubitors fought in several campaigns during the following centuries, and are last attested in the disastrous Battle of Dyrrhachium in 1081 that destroyed the remnants of the middle-Byzantine army.
History
Early period: Imperial bodyguard
The Excubitors were founded by Emperor Leo I in and were 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.File:Tremissis-Justin I-sb0058.jpg|thumb|right|250px|Tremissis of Emperor Justin I, the first commander of the Excubitors to rise to the throne.
The unit was headed by the count of the Excubitors, who was entirely independent of all other officials and subordinated only to the emperor himself. By virtue of his proximity to the emperor, the count of the Excubitors became an official of great importance in the 6th and 7th centuries. This post, which can be traced up to, 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, who held the post at the time of the death of Anastasius I, his elevation to the throne. Similarly, Justin II 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. He too would be succeeded by his own comes excubitorum, Maurice. Under Maurice, the post was held by his brother-in-law Philippicus, and under Phocas by Priscus. Another powerful occupant was Valentinus, who secured it during the power struggles that accompanied the regency of Empress-dowager Martina in 641, before deposing her and her son Heraklonas and installing Constans II as emperor. Valentinus dominated the new regime, but his attempt to become emperor himself in 644 ended in his being lynched by the mob.
By the late 6th century, the count of the Excubitors held the highest court ranks, of patrikios and vir gloriosissimus. Apart from their duties as commander of the Excubitors, holders of the office now also undertook other functions such as recruiting troops and interrogating suspected traitors. The count of the Excubitors was even sent to lead campaigns. The power that went with the position, and the intrigues of men like Priscus and the would-be usurper Valentinus, doomed the post to eventual decline during the latter half of the 7th century, although it is likely that the post continued in existence into the 8th century, until the corps was reorganized.
The participation of the Excubitors in campaigns is well attested, such as in 598, when Emperor Maurice took them to defend the Anastasian Wall against the Avars. They served with Heraclius against the Sasanian Persians, and some Excubitors appear as guards to Pope Martin I. During the later 7th century, like the Scholae before them, the Excubitors degenerated to a parade-ground unit that saw no active service. Indeed, it appears that during the 7th and early 8th centuries, the titles of excubitor and scribon were awarded as court dignities, paralleling the development of similar formerly military titles such as kandidatos. This is evidenced by a large number of seals naming individual excubitors during this time, in stark contrast to the periods before and after, when the Excubitors are attested as an active military unit. Furthermore, in many of these seals, individual excubitores—as well as scribones—are shown to have conjointly held bureaucratic offices, while at least one seal is known of a certain George, who was both excubitor and a scholarius.
Later period: Elite regiment
After being mentioned in a letter by Justinian II to Pope John V in 687, the Excubitors as a corps disappear from the historical sources until they re-emerge, under a new commander, the domestic of the Excubitors and in a new capacity, as one of the imperial, which comprised the elite professional central army established by Constantine V in. The were cavalry units, armed and equipped by the imperial arms factories to a higher standard than the provincial forces, likely including horse armour. As such the Excubitors were no longer a palace guard, but a unit actively engaged in military campaigns. At the same time, the, being loyal to the emperor's person, represented a counterbalance to the thematic armies of the provinces and constituted a powerful tool in implementing the iconoclastic policies pursued by Constantine V. Their original role as palace guardians was taken over by another, newly created, that of the.Nevertheless, the possibly first commander of the, Strategios Podopagouros, was among the leaders of a failed plot against Constantine V's life in 765, and was executed after its discovery. This initiated a purge of the new units from suspected opponents of the Emperor's policies. By the 780s, following years of imperial favour and military victories under Constantine V and his son Leo IV the Khazar, the had become firm adherents to the iconoclast cause. Within less than two months of Leo V's death in 780, Empress-regent Irene of Athens had to foil an attempt spearheaded by the Domestic of the Excubitors to place Constantine V's exiled second son, Nikephoros, on the throne, and in 785/86 Irene forcibly disarmed them and exiled some 1,500 tagmatic soldiers due to their resistance to the restoration of the icons.
At the same time, the were extensively employed in campaigns during this period: their participation is attested at least for Constantine V's 773 campaign against the Bulgars, and during the Abbasid invasion of [Asia Minor (782)|Abbasid invasion of Asia Minor] in 782. Indeed, the historian John Haldon remarks that the retention of the by Irene, despite their iconoclastic bias, is testament to their effectiveness as a field force. The Scholae and the Excubitors nevertheless continued to play an active political role in the events of the following decades: in 792, they attempted to overthrow Irene's son, Constantine VI, after the disastrous Battle of Marcellae against the Bulgars, and in 797, their support was crucial for Irene's overthrowing her own son and replacing him as sole ruler; and again, the two were crucial in the deposition of Irene herself in 802.
The Excubitors took part in the disastrous Pliska campaign in 811, when the Byzantine army was routed by Tsar Krum of Bulgaria ; the Domestic of the Excubitors fell in the field along with the other senior Byzantine generals, including Emperor Nikephoros I himself. The most prominent domestic of the Excubitors of the period was Michael II the Amorian, whose supporters overthrew Emperor Leo V the Armenian and raised him to the throne. The regiment also fought at the battles of Boulgarophygon in 896 and Acheloos in 917, both heavy defeats against the Bulgarians. In the expedition against the Emirate of Crete in 949, the Byzantine force included a contingent of over 700 Excubitors. In 958, the Excubitors participated in the repulsion of a Magyar raid.
The Excubitors took part in the failed Azaz campaign of 1030, where they were ambushed and dispersed by the Mirdasids, while their commander, the Leo Choirosphaktes, was taken captive. As with most of the Byzantine army, the of the capital atrophied during the mid-11th century, and many of them disappear in the turmoils of foreign invasion and civil wars that followed the destruction of the Byzantine field army in the Battle of Manzikert in 1071. The Excubitors are last attested in Anna Komnene's Alexiad, where they are recorded as participating at the Battle of Dyrrhachium against the Italo-Normans in 1081, under the command of Constantine Opos.
Structure
Early period
The internal structure of the regiment during its first centuries is obscure. Unlike the Scholae, which comprised several sub-units garrisoned throughout Bithynia as well as Constantinople, the Excubitors were a small and elite unit that served in the imperial palace itself and was intended exclusively to protect the emperor. From their foundation and throughout the early period of their existence, the Excubitors numbered 300 men. Originally recruited exclusively from Isaurians, the unit was eventually opened up to other ethnicities, but it is unclear how the new recruits were chosen. Based on the retention of late antique ranks in the middle Byzantine period, the Excubitors appear to have been structured similarly to the Scholae. Their arms and equipment are unknown, other than that they are recorded as carrying maces. Since they were a bodyguard unit intended to serve in the palace, they were most likely infantry.The presence of officers called scribones in the corps has been controversial: John B. Bury and A. H. M. Jones both suggested that they were a separate, although possibly related, unit. Based on the presence of the scribones among the ranks of the later, middle Byzantine incarnation of the Excubitors, however, it is thought that the scribones were the subaltern officers of the count of the Excubitors. The historian Warren Treadgold speculates that they fulfilled a role similar to the regular cavalry decurions, commanding troops of 30 men each, but the scribones also appear in charge of administrative matters such as handing out pay to the soldiers, as well as more sensitive tasks such as delivering letters, making arrests, and preparing expeditions.
Later period
In its later incarnation as a, the regiment was structured along the same standardized lines followed by the other, with a few variations in the titles of its officers.Commander
The regimental commander, the domestic of the Excubitors, is well attested in the various lists of offices in the 9th–10th centuries, where it is held in tandem with that of the chief of the "suburban" members of the racing faction of the Greens, which functioned as a militia for the defence of Constantinople, and of the regiment of the "Walls". The domestics were originally of strikingly low court rank, but they gradually rose to importance: while in the Taktikon Uspensky of the domestic of the Excubitors came behind all the thematic commanders in order of precedence, in the Klētorologion of 899, the domestic is shown as superior to the of the European themes and even to the Eparch of Constantinople. At the same time, the court dignities they held rose to the much loftier ranks of and even .The Escorial Taktikon, written, records the existence of a "Domestic of the Excubitors of the East", and a "Domestic of the Excubitors of the West", as well as a subaltern "Domestic of the Excubitors". This has led to the suggestion that, probably under Romanos II, the regiment, like the senior Scholae, was split in two units, one for the West and one for the East, each headed by a respective domestic. However, unlike the Scholae, these designations no longer appear in any later source, and they may have been of brief existence. The subaltern domestic of the Excubitors may either by a copyist error, or, according to Vera von Falkenhausen, indicate a subordinate official in charge of Excubitors stationed in the provinces; indeed such provincial detachments are attested, albeit only for the themes of Longobardia in southern Italy and of Hellas in Greece.
Other officers
The fact that the unit did not partake in campaigns during the 7th century preserved it from the reforms that affected the field army during this period, so that the late antique terminology for its junior officers remained relatively intact. The domestic was assisted by a and a . The was of relatively low-to-middle court rank. He may have commanded provincial detachments of the regiment, and there may have been more than one at the same time, for each of these detachments.Based on a reference from the hagiography of St. Joannicius the Great, who was himself recruited into the regiment and served there until deserting it following the Battle of Marcellae, in 773 the regiment itself was divided into at least eighteen, probably each commanded by a , showing the retention of the role of the earlier scribones as the main subaltern officers of the regiment. Each was further divided into sub-units headed by a . The post was originally that of a standard-bearer, but after Constantine V's reform of the unit into a, the probably functioned as junior officers. The junior officers also included the , and . There were also the usual messengers under a, some of whom were also termed , possibly entrusted with police duties.