A VERY Short Synopsis of the History of Dioecesis Britannia

A VERY Short Synopsis of the History of Dioecesis Britannia

Most of which appear again in the ‘Timeline of the Brithons’ which makes up the bulk of this work.

In 150 CE, Claudius Ptolemaeus of Alexandria published his Geographike Hyphegesis, including lists the known tribes, at least the major ones, of the Pretanic Isles, which were in large part the same as found during the Roman conquest.  These were, with additions from others contemporary sources (Julius Caesar, for example), as follows, by region:

Pictavia: Caereni, Caledonii, Carnonacae, Catti, Cornovii, Creones, Decantes, Epidii, Horestii, Lugi, Smertae, Taexali, Vacomagi, and Venicones

Between the Walls: Damnonii, Gadeni, Novantae, Selgovae, Votadini

North Britain: Anavionenses, Brigantes, Carvetti, Corionototae, Gabrantovices, Lopocares, Segontiaci, Setantii, and Textoverdi

Midlands: Cornovii, Corieltauvi, and Parisii

Southern Britain: Ancalites, Atrebates, Belgae, Bibroci, Boduni, Cantiaci, Cassi, Catuvellauni, Cenimagni, Iceni, Regnenses, and Trinovantes

West Country: Dobunni, Dumnonii, Durotriges, and Lendiniae (or Lendinienses, a subtribe of the Durotriges); there may have been also a third group of Cornovii as a subtribe of the Dumnonii, but evidence for that is tenuous.

North Wales (or ‘Deheubarth’, Cambria, modern Wales): Deceangli, Demetae, Gangani, Ordovices, and Silures

Since it is part of the Pretanic Isles, here are those of Ireland:

Ireland: Autini, Brigantes, Cauci, Corionidi, Darini, Eblani, Erdini, Gangani, Iverni, Manapii, Nagnatae, Robogdii, Usdaie, Vennicnii, Volunti, and Velabri

Also, these two regions became homes to diapora Brithons in the Late Roman and Early Medieval periods.

Armorica: Curiosolites, Osismii, Veneti, Redones, Namnetes

Gallaecia:  Arrotrebae (also spelled Arroni)

== Roman Britannia ==

Provincia Britanniae was first established in 43 CE, with its capital at Camulodunum, the former seat of the Trinovantes.  However, this was destroyed completely during Boudica’s War, and in the restoration after the war, the capital was moved to Londinium (London, Middlesex; Cair Lundein to the Brittones in the Sub-Roman period) on River Thames.

After Agricola finished his conquests, the province was sectioned into civitates based more or less on tribal realms (at least of the larger tribes or confederations), with the following capitals:

Calleva Atrebatum (Silchester, Hampshire); Cair Celemion
Venta Belgarum (Winchester, Hampshire); Cair Guinntguic
Isurium Brigantum (Aldborough, Yorkshire); Cair Isurion
Durovernum Cantiacorum (Canterbury, Kentshire); Cair Ceint
Durobrivae Cantiacorum (Rochester, Kentshire); Cair Dourbruf
Luguvalium Carvetiorum (Carlisle, Cumberlandshire); Cair Lugualid
Verulamium Catuvellaunum (St. Alban’s, Herefordshire); Cair Minicip
Ratae Corieltavarum (Leicester, Leicestershire); Cair Lerion
Viroconium Cornoviorum (Wroxeter, Shropshire); Cair Guricon
Moridunum Demetarum (Carmarthen, Carmarthenshire); Cair Merddyn
Corinium Dobunorum (Circencester, Gloucestershire); Cair Ceri
Isca Dumnoniorum (Exeter, Devonshire); Cair Uisc
Lendiniae Durotrigum (Ilchester, Somersetshire); Cair Lindinos
Durnovaria Durotrigum (Dorchester, Dorsetshire); Cair Durnac
Isca Dumnoniorum (Exeter, Devonshire); Cair Uisc
Venta Icenorum (Caistor St. Edmund, Norfolkshire); Cair Went
Petuaria Parisorum (Brough-on-Humber, Yorkshire); Cair Petuar
Noviomagus Regnensium (Chichester, Sussexshire); Cair Cei
Venta Silurum (Caerwent/Chepstow, Monmouthsire); Cair Guent
Caesaromagus Trinovantum (Chelmsford, Essexshire); Cair Calmer

In addition to the capitals of the civitates, four coloniae for veterans of the Roman army were established:

Colonia Claudia Victricensis, or Camulodunum (Colchester, Essexshire); Cair Colun
Colonia Domitiana Lindensium, or Lindum Colonia (Lincoln, Lincolnshire); Cair Lind-colun
Colonia Nervia Glevensium, or Glevum (Gloucester, Gloucestershire); Cair Gloui
Colonia Eboracensis, or Eboracum (York, Yorkshire); Cair Ebrauc

Some other major cities and towns with known Roman names:

Alauna (Alcester, Warwickshire); Cair Alen
Andertitum (Pevensey, Sussexshire); Cair Pensa vel Coyt, Anderidos
Aquae Sulis (Bath, Somersetshire); Cair Baddan
Blestium (Monmouth, Monmouthshire); Cair Guorthigirn
Caistor (Caistor, earlier Thancaster, Lincolnshire);
Castra ad Alaunam (Lancaster, Lancashire)
Cataractonium (Catterick, Yorkshire); Cair Catarauc
Canovium (Caerhun, Caernarfonshire); Cair Conovion
Danum (Doncaster, Yorkshire); Cair Daun
Deva Victrix (Chester, Chestershire); Cair Legion
Dubris (Dover, Kentshire); Cair Dour
Durolinponte (Cambridge, Cambridgeshire); Cair Grauth
Isca Augusta (Caerleon, Monmouthshire); Cair Legion-guar-Uisc
Letocetum (Wall, Leicester, Staffordshire); Cair-luit-Coyt
Magnae Dobunorum (Kenchester, Herefordshire); Cair Fawydd
Mamucium (Manchester, Lancashire); Cair Maunguid
Mediolanum (Whitechurch, Shropshire); Cair Meguidd
Moridunum (Carmarthen, Carmarthenshire); Cair Merddyn
Portus Adumi (Portsmouth, Hampshire); Cair Portus
Rutupiae (Richborough, Kentshire); Cair Ritus (?)
Segontium (Caernarfon, Caernarfonshire); Cair Segeint
Sorviodunum (Old Sarum, Salisbury, Wiltshire); Cair Caratauc
Tamium (Cardiff, Glamorganshire); Cair Taf
Vertis (Worcester, Worcestershire); Cair Guiragon
Verulamium (St. Albans, Hertfordshire); Cair Mincip
Vinovia (Binchester, County Durham); Cair Weir

* * * * *

After Severus Augustus defeated Albinus at the Battle of Lugdunum in 197, he sent Virius Lupus as Propraetor Britanniae, dividing the single province of Britannia into two (each under a legatus Augusti pro praetore):  Britannia Superior, with its capital at Londinium, and Britannia Inferior, with its capital at Eboracum.

* * * * *

In 297, following the collapse of the ‘Imperium Brittanicum’, Caesar Constantius Chlorus divided Britannia Superior and Britannia Inferior into four new provinces, making it a diocese headed by a vicarius under the Praefectura Praetorio Galliae: Britannia Maxima Caesariensis, with its capital at Londinium; Britannia Prima, with its capital at Corinium; Britannia Secunda, with its capital at Eboracum; and Britannia Flavia Caesariensis, with its capital at Lindum.

The governor of the first was a consularis, of the other three were praesides; Britannia Maxima covered the densely-populated southeast; Britannia Prima roughly what became (North) Wales along with the West Country; Britannia Flavia the area of the later midlands Mercia; and Britannia Secunda the part of later Northumbria south of Hadrian’s Wall.  In addition, Londinium, the capital of the diocese as well as of Britannia Maxima, was renamed Augusta Britanniarum, though the redesignation never gained widespread usage.

These governors only had authority over civilian affairs, with no military units attached to their offices, but this now was the case with all civil officers, not just those in frequently rebellious Brittania.  The military in the diocese was restructured as follows:

In Dioecesis Britanniae, there were three commands: 

Comes Maritimi Tractus, under whom were Legio II Augusta, now at Ritupiae (Richborough), plus limitanei that include 3000 foot and 600 horse

Dux Britanniarum, under whom were Legio VI Victrix at Eboracum, plus limitanei that include 14,000 foot and 900 horse

Comes Britanniae (Comes Rei Militaris per Britannias), under whom were Legio XX Valeria Victrix at Deva Victrix, plus comitatenses that include 2200 foot, 200 horse

The Comes Maritimi Tractus (later Comes Litoris Saxonici per Britanniam) supervised shore defense of both sides of the Mare Britannicum (English Channel) and also had under his command the Classis Britannica, which is based at both Dubris (Dover) in Britannia and at Bononia (Boulogne-sur-Mer) in Gallia.

In the same reform, the provinces of Gaul were divided into the Diocese of Galliae (Lugdunensis I, Lugdunensis II, Lugdunensis III, Lugdunensis IV Senonia, Belgica I, Belgica II, Germania I, Germania II, and Maxima Sequanorum) and the Diocese of Viennensis or Septem Provinciae (Aquitania I, Aquitania II, Aquitania III Novempopulana, Narbonensis I, Narbonensis II, Viennensis, Alpes Maritimae, and Alpes Poeninae et Graiae).

In Hispania, the three provinces became five: Hispania Tarraconensis, Hispania Gallaecia, Hispanis Lusitania, Hispania Baetica, and Hispania Cartaginensis.  Furthermore, the provinces here were further subdivided into ‘conventi’, a counterpart to the civitates of the rest of the empire.

* * * * *

At the death of Constantinus Augustus in 337, the Imperium Romanum was divided into three praefecturae praetoriae (with their dioceses):

Praefectura Praetorio Galliarum: Gallia, Viennensis or Septem Provinciae, Britannia, Hispania, Germania, and Tingitana

Praefectura Praetorio Italiae, Illyrici, et Africae: Italia, the Balkans, and Africa

Praefectura Praetorio Orientis: Thracia, Anatolia, Syria-Palestina, Aegyptus, and Libya

As was the case with civilian diocesan and provincial officials in the reorganization of 297, the Praefecti of these units had authority only over civil administration.

This tripartite division corresponded to the territories alotted to the three sons and surviving successors of Constantinus I Augustus: Flavius Claudius Constantinus (Constantine II) over Galliae, Flavius Julius Constans over Italiae, and Flavius Julius Constantius (Constantius II) over Orientis.

In addition to these regions, Roma and Constantinopolis each have their own Praefectus.

The Magister Militum per Gallias reported to the Magister Utriusquae Militiae, who answers to the western Augustus.

* * * * *

Mopping up operations in the north in the wake of the Great Conspiracy of 367, Vicarius Britanniae Civilus added an additional province in the north, Britannia Valentia, making its governor a consularis.  For centuries, general hypothesis held this to be between the Walls (‘Intermuros’, the Walls being Hadrian’s and the Antonine), with its seat at Habitanicum (Risingham, Northumberlandshire) on Dere Street, or else at Luguvalium (Carlisle).  Since the late 20th century, dissenting opinions have suggested it was rather in Wales, with its seat at Deva, or else covered Cumberlandshire-Westmorelandshire, with its seat at Luguvalium.

Notitia Dignatum, 425

The portion dealing with Britannia, and two associated commands in northern Gallia.

At the top of Dioecesis Britanniae is the Vicarius (Vices Agens Praefecti Praetorio Galliarum per Britannias).  His staff includes a princeps officium (chief of staff), a cornucularius (chief deputy), two numerarii (receivers of taxes), a commentariensis (keeper of the commentary or diary), an adiutor (chief assistant), an ab actis (acts keeper, archivist), a cure epistolorum (keeper of correspondence), subadiuvae (deputy assistants), exceptores (lower clerks), and singulares et reliquum officium (various menial staff).

At the next level are the governors of provinces.  Those of Britannia Prima and Britannia Valentia each have a consularis, while those of Britannia Secunda, Britannia Flavia Caesariensis, and Britannia Maxima Caesariensis each have a praesides, which, if the Nomina Omnium Provinciarum of Polemius Silvanus (449) is accurate, would have also been the case with Britannia Orcades.  Each of the governors has a similar staff to the vicarius.

In addition to reaffirming the five province structure of the diocese, the ND lists the following military commands.  In the late Roman army, a numerus was a unit of 300.  A cohort was a unit of 480.  An ala was a special cavalry unit.  The legion of the late Roman army had 1000 infantry soldiers rather than the 5000 mostly infantry supported by cavalry of earlier.

Many of the local and tribal designations along with specialized functions such as ‘exploratorum’ and ‘vigilum’ were traditional and may have had little to do with the actual origin, composition, or duties at this date.

The ND did not include Roman forts in Valentia (between the Walls) nor in  (North) Wales, probably because, as noted above, these had previously been turned over to ‘praefectus gentili’ (local rulers and/or Roman officers).

Comes Rei Militaris per Britannias (Comes Britanniae)

Includes overall military command of Dioecesis Britanniae, with direct charge of the comitatus, or field army, of which are the following units:

Primani iuniores (formerly half of Legio II Adiutrix)
        (legiones comitatenses; heavy infantry)
Secundani iuniores (formerly half of Legio II Adiutrix)
        (legiones comitatenses; heavy infantry)
Victores iuniores Britanniciani
        (an auxilia palatinae; medium infantry)
Equites cataphractarii iuniores
        (heavy cavalry)
Equites stablesiani
        (heavy cavalry)
Equites scutarii Aureliaci
        (heavy cavalry)
Equites Honoriani seniores
        (a vexillationes comitatenses)
Equites Syres
        (mercenary cavalry)
Equites Taifali
        (mercenary cavalry)

Comes Litoris Saxonici per Britanniam

Includes command over the limitanei on the northern coast of the Oceanus Britannica and the eastern coast of the Mare Frisicum

Praefectus legionis II Augustae, Rutupis
        (Richborough, Kentshire)
Praefectus classis Britannicae, Dubris
        (Dover, Kentshire)
Praepositus numeri Fortensium, Othonae
        (Bradwell, Essexshire)
Praepositus militum Tungrecanorum, Dubris
        (Dover, Kentshire)
Praepositus numeri Turnacensium, Lemannis
        (Lympne, Kentshire)
Praepositus equitum Dalmatarum Branodunensium, Branoduno
        (Brancaster, Norfolkshire)
Praepositus equitum stablesianorum Gariannonensium, Gariannonor
        (Burgh Castle, Norfolkshire)
Tribunus cohortis primae Baetasiorum, Regulbio
        (Reculver, Kentshire)
Praepositus numeri Abulcorum, Anderidos (Andertitum)
        (Pevensey, Sussexshire)
Praefectus classis Anderidaensis, Anderdidos
        (Pevensey, Sussexshire)
Praepositus numeri exploratorum, Portum Adurni
        (reconnaissance; Portchester, Hampshire)

Dux Britanniarum

Includes command over the limitanei in Maxima Caesariensis and along the Vallum Aelium (Vallum Hadriani, Hadrian’s Wall), with some authority over Valentia and possibly over Britannia Secunda.

Praefectus legionis VI, Eboracum
        (York, Yorkshire)
Praefectus equitum Dalmatarum, Praesidio
        (near Bridlington, Humberside)
Praefectus equitum Crispianorum, Dano
        (Doncaster, Yorkshire)
Praefectus equitum catafractariorum, Morbio
        (Ilkley, Yorkshire)
Praefectus numeri barcariorum Tigrisiensium, Arbeia
        (South Shields, County Durham)
Praefectus numeri Nevuiorum Dictensium, Dicti
        (Old Winteringham, Lincolnshire)
Praefectus numeri vigilum, Concangios
        (“watchmen”; Chester-le-Street, County Durham)
Praefectus numeri exploratorum, Lavatres
        (Bowes, County Durham)
Praefectus numeri directorum, Verteris
        (“guides”; Brough Castle, Westmorlandshire)
Praefectus numeri defensorum, Barboniaco
        (“defenders”; Kirkby Thore, Westmorlandshire)
Praefectus numeri Solensium, Maglone
        (Old Carlisle, Cumberlandshire)
Praefectus numeri Pacensium, Magis
        ( Drumburgh, Cumberlandshire)
Praefectus numeri Longovicanorum, Longovicio
        (Lanchester, County Durham)
Praefectus numeri supervenientium Petueriensium, Deruentione
        (Malton, Yorkshire)

Units along the Wall:

Tribunus cohortis quartae Lingonum, Segeduno
        (Wallsend, Northumberlandshire; Segedunum)
Tribunus cohortis primae Cornoviorum, Ponte Aeli
        (Newcastle, Northumberlandshire; Pont Aelius)
Praefectus alae primae Asturum, Conderco
        (Benwell, Northumberlandshire)
Tribunus cohortis primae Frixagorum, Vindobala
        (Rudchester, Northumberlandshire)
Praefectus alae Sabinianae, Hunno
        (Halton Chesters, Northumberlandshire; Onnum)
Praefectus alae secundae Asturum, Cilurno
        (Chesters, Northumberlandshire; Cilurnum)
Tribunus cohortis primae Batavorum, Procolitia
        (Carrawburgh, Northumberlandshire; Brocolitia)
Tribunus cohortis primae Tungrorum, Borcovicio
        (Housesteads, Northumberlandshire; Vercovicium)
Tribunus cohortis quartae Gallorum, Vindolana
        (Chesterholm, Northumberlandshire; Vindolanda)
Tribunus cohortis primae Asturum, Aesica
        (Great Chesters, Northumberlandshire)
Tribunus cohortis secundae Dalmatarum, Magnis
        (Carvoran, Northumberlandshire)
Tribunus cohortis primae Aeliae Dacorum, Amboglanna
        (Birdoswald, Cumberlandshire; Camboglanna)
Praefectus alae Petrianae, Petrianis
        (Stanwix or Wreay, Cumberlandshire; Vxelodunum)
Praefectus numeri Maurorum Aurelianorum, Aballaba
        (Burgh-by-Sands, Cumberlandshire)
Tribunus cohortis secundae Lingonum, Congavata
        (Kirkbride or Drumburgh, Cumberlandshire)
Tribunus cohortis primae Hispanorum, Axeloduno
        (Maryport or Netherby, Cumberlandshire; Castra Exploratorum)
Tribunus cohortis secundae Thracum, Gabrosenti
        (Workington or Moresby, Cumberlandshire)
Tribunus cohortis primae Aeliae classicae, Tunnocelo
        (Bowness or near Calder Bridge, Cumberlandshire)
Tribunus cohortis primae Morinorum, Glannibanta
        (Ravenglass, Cumberlandshire)
Tribunus cohortis tertiae Neruiorum, Alione
        (Lancaster, Lancashire; Calunium)
Cuneus Sarmatarum, Bremetenraco
        (Ribchester, Lancashire; Bremetenacum)
Praefectus alae primae Herculeae, Olenaco
        (Elslack, Yorkshire; Olenacum)
Tribunus cohortis sextae Neruiorum, Virosido
        (Brough-by-Bainbridge, Yorkshire; Virosidum)

The following two commands of territory in Dioecesis Galliae on the Continent, districts formerly under the Comes Maritimi Tractus, coordinate with the Comes Litoris Saxonici but are not under his command

Dux Tractus Armoricani et Nervicani

Includes command over the limitanei in Lugdunensis II, Lugdunensis III, Lugudnensis IV Senonia, Aquitania I, & Aquitania II, with shore and inland territory stretching from the mouth of Gironde Estuary in Aquitaine to the mouth of River Somme in Picardy.

Tribunus cohortis primae novae Armoricanae, Grannona in litore Saxonico
        (Port-en-Bessin, France)
Praefectus militum Carronensium, Blabia
        (Blaye, France)
Praefectus militum Maurorum Benetorum, Venetis
        (Vannes, Brittany)
Praefectus militum Maurorum Osismiacorum, Osismis
        (Brest, Britanny)
Praefectus militum superventorum, Mannatias
        (Nantes, Britanny)
Praefectus militum Martensium, Aleto
        (Saint-Malo-de-Beignon, Britanny)
Praefectus militum primae Flaviae, Constantia
        (Countances, Normandy, France)
Praefectus militum Ursariensium, Rotomagus
        (Rouen, Normandy, France)
Praefectus militum Dalmatarum, Abrincatis
        (Avracnes, Normandy, France)
Praefectus militum Grannonensium, Grannona
        (Port-en-Bessin, France)

Dux Belgicae Secundae

The following three units were originally assigned to this command but later detached to the field army of the Magister Militium per Gallias:

Geminiacenses
        (legiones comitatenses; heavy infantry)
Cortoriacenses
        (legiones comitatenses; heavy infantry)
Prima Flavia Metis
        (legiones pseudocomitatenses; heavy infantry, former limitanei)

Includes command over the limitanei in Belgica Secunda and over the Classis Sambricae (which operated on the River Somme and the Mare Frisicum near the mouth)

Equites Dalmatae, Marcis in litore Saxonico
        (prob. Marck, France; Marquise or Mardyck also poss.)
Praefectus classis Sambricae, in loco Quartensi siue Hornensi
        (Port d’Etaples and Cap Hornu or Saint-Valery-sur-Somme)
Tribunus militum Nerviorum, Portu Epatiacus
        (Oudenberg, Netherlands)
Praefectus laetorum Nerviorum, Fanomantis
        (Famars, Picardie, France)
Praefectus laetorum Batavorum Nemetacensium, Atrabatis
        (Arras, Pas de Calais, France)
Praefectus laetorum Batavorum Contraginnensium in Noviomago
        (Nijmegen, Netherlands)
Praefectus laetorum gentilium in Remo et Silvanectas
        (Durocotroum Remorum, now Riennes, and Senlis, France)
Praefectus Sarmatarum gentilium inter Renos et Tambianos
        (between Renos and Tambianos)