Roman Military Sites in Britain

The army's role remained much the same in the late Empire as it had been in the earlier perios: policing frontier tribes; preventing cattle rustling and tax evasion; and showing the flag to allied tribes in the border region. However the increasing sophistication of the tribes outside the Empire, caused in some ways by the presence and success of the Empire itself, meant that wars in the later Empire, when they erupted, were hard-fought affairs against increasingly larger confederacies of tribesmen, armed with weapons as effective as those of the Roman army. These wars and in particular the chaos of the 3rd century led to units being destroyed and vexillations failing to return to their home units and becoming independent units. It is out of this period of instability that the army of the late Empire appears.

Late-Empire heavy cavalryman

Late-Empire infantryman

Late-Empire standard bearer

From the 3rd century onwards major threats were often met within the Empire although punitive raids continued to be mounted almost until the end of the Western Empire. In Britain expeditions into at least southern Scotland were mounted right upto the end of the 4th century.

As the opposing tribes coalesced into larger and more organised groupings they often became too powerful for the army to be strong enough everywhere on the limes to meet the threat. This in turn required standing field armies at key points away from the frontier. The old system of creating field armies for major campaigns from vexillations of legionary and auxiliary troops began to be supplemented by small standing field armies accompanying the Emperor. In time this lead to two types of army unit: frontier troops (limitanei) and higher grade field armies (comitatus). It appears that the practice of using vexillations led to the reduction in size of legions in the late Empire and in the duplication of units with the same or similar names that originated from one original.

The change in strategy appears to start with Septimus Severus who for the first time stationed one of his new legions, Legio II Parthica, in Italy as a mobile reserve along with the Praetorian Guard and Urban Cohorts. Gallienus in the mid third century created cavalry vexillations from the cavalry elements of the legions to give him a more mobile strike force. Diocletian makes the last attempt to strengthen the frontier by raising extra legions and auxiliary units, whilst maintaining small field armies for each of his colleagues in the Tetrarchy.

The final system emerges under Constantine. Frontier troops - the limitanei made up of old-style alae and cohorts, supported by the legions plus new style cavalry and infantry auxilia, with field armies the comitatus (from the companions who accompanied the Emperor) consisting of regiments, some derived from the existing legions. Originally the comitatus was under the Emperor's command, but during the fourth century field armies were created under the command of Dux and Comes within provinces. The British section of the Notitia lists the Comes Britanniarum as commanding six cavalry and three infantry units of the comitatus.

Types of regiments

The third century changes were matched by an increasing variety of names for regiments. Units become smaller with field army regiments at around 1,000 for infantry and 500 for cavalry and the limitanei at around 300. It is unclear if this happened under Diocletian or Constantine, or indeed whether it was a deliberate change or just the result of downgrading the importance of the limitanei and the creation of field army units from the old legion and auxiliary vexillations. For example it is probable that the Legio Secundani Britones recorded in the Notitia was derived from a vexillation of the II Augusta.

UNIT TYPES: INVASION TO NOTITIA

The names and roles of units changed from the invasion when the whole army was a 'field army' until the early 5th century when the divisions between the major field army under the control of the Emperor or his senior general, local field armies in provinces and the frontier troops had become established. The names of types of units changed or in some cases old style names were used to describe different troops. Fifth century auxilia were higher grade troops than the auxiliaries of the earlier period and field army units described formally as separate vexillations from the early third century are usually cavalry, however limitanei vexillationes could be infantry. In the historical record many units are known by only part of their name, for example Seguntienses, a unit once based at Segontium (Caernarfon) and in the Notitia recorded as part of the field army of Illyricum.

Invasion 43 AD

Praetorians
Singulares
Legio
Alae
Cohors equitata
Cohors peditata
Classis

Notes
Constantine disbands the Praetorians and replaces them with the Scholae.

By the 5th century legions are 1,000 strong, in the early Empire they are around 5,5000 strong, when the reduction in size was made is not clear.

Numerus and Cunea are small units of around 200 men commanded by legionary centurions. Numerus had always been used as a generic term for military units, but by the 5th century they were used as the formal title for units.

Auxilia are high status infantry units and are different from earlier auxilia.

Pseudocomitensis are units upgraded by transfer from the limitanei.

Regimental names in the late army

Units continue to have names that reflect their origins. Equites Dalmatae Branudunenses were raised in what is now Croatia around the middle of the third century and based at the Saxon Shore fort of Branodunum (Brancaster on the Norfolk coast). However sources increasingly use shorter names and many late regiments have titles combining 'unit' - Numerus - and their location or origin, for example Numerus Turnacensium, originally based at Tournai and listed in the Notitia as the garrison of Lympne.

THE NAVY OF THE LATE EMPIRE

The old-style regional fleets appear to disappear under the late Empire, although the eastern Empire is still able to send invasion forces to Africa, Italy and Spain in the 6th century, presumably using navies similar to the one that delivered the invasion force to Britain almost 500 years before. In Britain it is possible the Classis Britannica may have been split into smaller units attached to the coastal forts and operating in concert with the fort's garrison as part of the limitanei. Such a unit was presumably Classis Anderetiana that is recorded in the Notitia Dignitatum as being based at Paris, but originated at Pevensey (Anderida).

Depending on the presumed role of the Saxon Shore forts the navy is either a fighting and reconnaissance force working in conjunction with fort garrisons or part of a system for transporting food and other materials to and from the European mainland via the fortified harbours of the Saxon Shore.



		Gazetteer of military sites in Britannia	THE ARMY OF THE LATE EMPIRE The structure of late Empire's army is much less well known. Information in Britain comes principally from archaeology, although since during the late Empire there is a reduction in inscriptions recording building work by the army, the evidence can be confusing. However the Notitia Dignitatum, a list of military and civil officials from the late Empire has survived. The Notitia dates from between the late fourth century and early 5th century. Sadly it omits some locations that from archaeology are known to have been occupied during this period. There is also considerable debate about the period when the British sections were compiled, nevertheless it offers a fascinating insight into the administrative sophistication of the Empire. The 1st & 2nd century army The navy Typical soldiers and units Military site plans and reconstructions Introduction
		Glossary of military terms
		Reading lists




			The army's role remained much the same in the late Empire as it had been in the earlier perios: policing frontier tribes; preventing cattle rustling and tax evasion; and showing the flag to allied tribes in the border region. However the increasing sophistication of the tribes outside the Empire, caused in some ways by the presence and success of the Empire itself, meant that wars in the later Empire, when they erupted, were hard-fought affairs against increasingly larger confederacies of tribesmen, armed with weapons as effective as those of the Roman army. These wars and in particular the chaos of the 3rd century led to units being destroyed and vexillations failing to return to their home units and becoming independent units. It is out of this period of instability that the army of the late Empire appears. Late-Empire heavy cavalryman Late-Empire infantryman Late-Empire standard bearer The growth of the field army From the 3rd century onwards major threats were often met within the Empire although punitive raids continued to be mounted almost until the end of the Western Empire. In Britain expeditions into at least southern Scotland were mounted right upto the end of the 4th century. As the opposing tribes coalesced into larger and more organised groupings they often became too powerful for the army to be strong enough everywhere on the limes to meet the threat. This in turn required standing field armies at key points away from the frontier. The old system of creating field armies for major campaigns from vexillations of legionary and auxiliary troops began to be supplemented by small standing field armies accompanying the Emperor. In time this lead to two types of army unit: frontier troops (limitanei) and higher grade field armies (comitatus). It appears that the practice of using vexillations led to the reduction in size of legions in the late Empire and in the duplication of units with the same or similar names that originated from one original. The change in strategy appears to start with Septimus Severus who for the first time stationed one of his new legions, Legio II Parthica, in Italy as a mobile reserve along with the Praetorian Guard and Urban Cohorts. Gallienus in the mid third century created cavalry vexillations from the cavalry elements of the legions to give him a more mobile strike force. Diocletian makes the last attempt to strengthen the frontier by raising extra legions and auxiliary units, whilst maintaining small field armies for each of his colleagues in the Tetrarchy. The final system emerges under Constantine. Frontier troops - the limitanei made up of old-style alae and cohorts, supported by the legions plus new style cavalry and infantry auxilia, with field armies the comitatus (from the companions who accompanied the Emperor) consisting of regiments, some derived from the existing legions. Originally the comitatus was under the Emperor's command, but during the fourth century field armies were created under the command of Dux and Comes within provinces. The British section of the Notitia lists the Comes Britanniarum as commanding six cavalry and three infantry units of the comitatus. Types of regiments The third century changes were matched by an increasing variety of names for regiments. Units become smaller with field army regiments at around 1,000 for infantry and 500 for cavalry and the limitanei at around 300. It is unclear if this happened under Diocletian or Constantine, or indeed whether it was a deliberate change or just the result of downgrading the importance of the limitanei and the creation of field army units from the old legion and auxiliary vexillations. For example it is probable that the Legio Secundani Britones recorded in the Notitia was derived from a vexillation of the II Augusta. UNIT TYPES: INVASION TO NOTITIA The names and roles of units changed from the invasion when the whole army was a 'field army' until the early 5th century when the divisions between the major field army under the control of the Emperor or his senior general, local field armies in provinces and the frontier troops had become established. The names of types of units changed or in some cases old style names were used to describe different troops. Fifth century auxilia were higher grade troops than the auxiliaries of the earlier period and field army units described formally as separate vexillations from the early third century are usually cavalry, however limitanei vexillationes could be infantry. In the historical record many units are known by only part of their name, for example Seguntienses, a unit once based at Segontium (Caernarfon) and in the Notitia recorded as part of the field army of Illyricum.

		Invasion 43 AD Praetorians Singulares Legio Alae Cohors equitata Cohors peditata Classis	Mid-2nd century Praetorians Singulares Legio Alae Cohors equitata Cohors peditata Numerus Cunea Classis

		Constantine 312 AD Comitatus Scholae Vexillationes Auxilia Legio Limitanei Legio Alae Cohors equitata Cohors peditata Numerus Cunea Classis	Notitia Dignitatum c 400AD Comitatus Scholae Vexillationes Auxilia Legio Pseudocomitensis Equites Other Field Army Vexillationes Auxilia Legio Pseudocomitensis Equite Limitanei Vexillationes Auxilia Legio Cunei Milites Equites Numerus Classis
		Notes Constantine disbands the Praetorians and replaces them with the Scholae. By the 5th century legions are 1,000 strong, in the early Empire they are around 5,5000 strong, when the reduction in size was made is not clear. Numerus and Cunea are small units of around 200 men commanded by legionary centurions. Numerus had always been used as a generic term for military units, but by the 5th century they were used as the formal title for units. Auxilia are high status infantry units and are different from earlier auxilia. Pseudocomitensis are units upgraded by transfer from the limitanei. Regimental names in the late army Units continue to have names that reflect their origins. Equites Dalmatae Branudunenses were raised in what is now Croatia around the middle of the third century and based at the Saxon Shore fort of Branodunum (Brancaster on the Norfolk coast). However sources increasingly use shorter names and many late regiments have titles combining 'unit' - Numerus - and their location or origin, for example Numerus Turnacensium, originally based at Tournai and listed in the Notitia as the garrison of Lympne. THE NAVY OF THE LATE EMPIRE The old-style regional fleets appear to disappear under the late Empire, although the eastern Empire is still able to send invasion forces to Africa, Italy and Spain in the 6th century, presumably using navies similar to the one that delivered the invasion force to Britain almost 500 years before. In Britain it is possible the Classis Britannica may have been split into smaller units attached to the coastal forts and operating in concert with the fort's garrison as part of the limitanei. Such a unit was presumably Classis Anderetiana that is recorded in the Notitia Dignitatum as being based at Paris, but originated at Pevensey (Anderida). Depending on the presumed role of the Saxon Shore forts the navy is either a fighting and reconnaissance force working in conjunction with fort garrisons or part of a system for transporting food and other materials to and from the European mainland via the fortified harbours of the Saxon Shore.