Dux Britanniarum



Dux Britanniarum was a military post in Roman Britain, probably created by Diocletian or Constantine I during the late third or early fourth century. The Dux (literally, "(military) leader") was a senior officer in the late Roman army of the West in Britain. It is listed in the Notitia Dignitatum as being one of the three commands in Britain, along with the


 * Comes Britanniarum and
 * Count of the Saxon Shore.

The Dux Britanniarum was commander of the troops of the Northern Region, primarily along Hadrian's Wall. At the imperial court the Dux had the highest ranking class of viri spectabiles.

His responsibilities covered the area along Hadrian's Wall, including the surrounding areas to the river Humber in the southeast of the city of Deva (Chester) and today's Yorkshire, Cumbria and Northumberland to the mountains of the Southern Pennines. The headquarters were in the city of Eboracum (York). The purpose of this buffer zone was to preserve especially the economically important and prosperous southeast of the island from attacks by the Picts (tribes of what are now the Scottish lowlands) and against Scots (Irish raiders).

History
The troubled north of the island was dominated by the military. The soldiers of the Dux were probably recruited almost exclusively in Britain. The Notitia Dignitatum lists the garrison along Hadrian's Wall (along with several sites on the coast of Cumbria) for a total of 38 units under the command of the Dux Britanniarum. Archaeological evidence shows that other units must have been stationed here, which are not, however, mentioned in the Notita. Most of them were established during the 3rd Century. (Long time was that these troops list because of the relatively large number of High Imperial unit designations for antiquated, only more so keepeh?) in Notita Dignitatum because Britain was never officially abandoned by the Romans.

Castles and units
His troops were limitanei or frontier guards and not the comitatenses or field army commanded by the Comes Britanniarum. Fourteen units in north Britain are listed in the Notitia as being under his command, stationed in either modern Yorkshire, Cumbria or Northumberland. Archaeological evidence indicates there were other posts occupied at the time which are not listed. His forces included three cavalry vexillationes with the rest being infantry. They were newly-raised units rather than being third century creations. In addition to these fort garrisons, the dux commanded the troops at Hadrian's Wall: the Notitia lists their stations from east to west, as well as additional forts on the Cumbrian coast. These troops appear to have been third century regiments, although the reliability of the Notitia makes it difficult to infer any solid information from it.

From Chapter XL:


 * sub dispositione viri spectabilis Ducis Britanniarum (literally "made available to the most honorable military commander of the British provinces")

...in addition to the administrative staff (Officium) lists 14 prefects and their units with their deployment locations under the command of this Dux:


 * Praefectus Legionis sextae
 * Praefectus Numeri directorum, Verteris
 * Praefectus Numeri exploratorum, Lavatrae
 * Praefectus Equitum Dalmatarum, Praesidio
 * Praefectus Equitum Crispianorum, Dano
 * Praefectus Numeri defensorum, Barboniaco
 * Praefectus Equitum, catafractariorum, Morbio
 * Praefectus Numeri Solensium, Maglone
 * Praefectus Numeri barcariorum Tigrisiensium, Arbeia
 * Praefectus Numeri Pacensium, Magis
 * Praefectus Numeri Nerviorum Dictensium, Dicti
 * Praefectus Numeri Longovicanorum, Longovicium
 * Praefectus Numeri vigilum, Concangis
 * Praefectus Numeri supervenientium Petueriensium, Deruentione (Derventio?)

Then follow the garrisons along Hadrian's Wall (per item lineam Valli):


 * Cohortis quaternary Lingonum, Segedunum
 * Tribune Alae Petrianae, Petriana
 * Praefectus cohortis primae Cornoviorum, Pons Aelius
 * Tribune Alae primae Asturum, Cilurnum or Cilurvum
 * Praefectus Numeri Maurorum Aurelianorum, Aballaba
 * Praefectus cohortis primae Frixagorum, Vindobala
 * Tribune cohortis secundae Lingonum, Segedunum
 * Tribune Alae Sabinianae, Hunnum or Onnum
 * Praefectus cohortis primae Hispanorum, Uxelodunum or Petriana
 * Tribune Alae secundae Asturum, Aesica
 * Praefectus cohortis secundae Thracum, Gabrosenti
 * Tribune cohortis primae Batavorum, Procolita
 * Tribune cohortis primae Aeliae Classicae, Tunnocelo
 * Tribune cohortis primae Tungrorum Classicae, Vercovicium
 * Tribune cohortis primae Morinorum, Glannoventa
 * Tribune cohortis quaternary Gallorum, Vindolanda
 * Tribune cohortis tertiae Nerviorum, Alione (Alauna?)
 * Tribune cohortis primae Asturum, Aesica
 * Cuneus Sarmatarum, Bremetenraco (Bremenium?)(no officer stated)
 * Cohortis secundae Dalmatarum, Magnis
 * Tribune Alae primae Herculeae, Olenaco
 * Praefectus cohortis primae Aeliae Dacorum, Camboglanna or Banna
 * Tribune cohortis sextae Nerviorum, Virosido

and an unknown unit in the fort Luguvalium

Origin
All these units are limitanei. (However, it seems that some have stood for the Comes Britanniarum available.eh?) The ultimate list of the Dux Britanniarum was completed well ahead of the Comes Britanniarum. One should, however, (not take the original edition of Notita Dignitatum literally?), as this would place one unit (Segontienses) at Segontium (Carnarvon in Wales). Since it is unlikely that field army units were used to reinforce remote garrisons, it appears the British limitanei were further reduced in order to fill them with the Gallic field army as Pseudocomitatenses.

(The Comes Britanniarum ("also seen as" - was also?) commander of a unit of Equites catafractarii iuniores, but oddly in the Notita (be?) Dignitatum not (as with a unit of Comitatenses usual) units of Equites catafractarii under the command of the Magister Equitum, is believed to that this unit is one and the same as that which is commanded according to the List Magister Equitum troops in Notita Dignitatum by Praefectus equitum catafractariorum. This unit appears only later - towards the end of Roman rule in Britain - established the Comes Britanniarum Army, have been assigned, and thus lost their permanent barracks.help!)

The Cuneus Sarmatarum was a cavalry unit recruited from Sarmatian horsemen.

The Equites Crispianorum may have been named for Crispus, eldest son of Constantine I, who was executed in 326 AD for an alleged conspiracy, by personal order of the emperor. The continued existence of his name in this unit (along with the Auxilium Crispitienses under the Dux Daciae) shows that he probably did not fall within the otherwise rigorously handled damnatio memoriae (i.e., removing all mention of the condemned's existence).

The men under the Praefectus Defensorum Numeri seem to be the same as the Defensores seniores (pseudocomitatensis from Gaul under the command of Master Equitum).

The men under the Praefectus Numbers exploratorum were reconnaissance and also a unit of Gallic Pseudocomitatenses (with a Master Equitum as commander), but also partly the stand Comes Litoris Saxonici available (stood available to the Commander of the Saxon Shore?)

The Legio sexta is an ancient tribal legion of Britain, the Legio VI Eburacum (York). Interestingly, they seem to have had in late antiquity no fixed posting. One might expect that this legion (full name: Legio VI Victrix Pia Fidelis Britannica) at this time still to be stationed in Eburacum: this absence may indicate that the unit had been moved to another site when the list of the Dux Britanniarum was compiled in the Notita Dignitatum. ("Possibly is the VI."?) but also in connection with the non-historically tangible primani iuniores in the army of the Comes Britanniarum.

The men under the Praefectus Numbers Solensium could (per Arnold Hughes Martin Jones, 1986) be the descendents of another British unit, the Legio XX Valeria Victrix. This is the only legion no longer listed in the Notita Dignitatum. The last epigraphic evidence of their presence in Britain is a mention on coins of the usurper Carausius, a century before the Notita Dignitatum was compiled.