Editing Roman Britain (section)

== History ==
=== Early contact ===
{{Main|Julius Caesar's invasions of Britain}}

Britain was known to the [[Classical world]]. The [[Ancient Greece|Greeks]], the [[Phoenicia]]ns and the [[Carthage|Carthaginians]] traded for [[Cornwall|Cornish]] [[tin mining in Britain|tin]] in the 4th century BC.<ref name="Welsh">{{Cite book |last=Patrick Welsh |first=George |title=Britannia: the Roman Conquest and Occupation of Britain |year=1963 |pages=27–31}}</ref> The Greeks referred to the ''{{Lang|grc-Latn|[[Cassiterides]]}}'', or "tin islands", and placed them near the west coast of Europe.<ref>{{Citation |author=[[Herodotus]] |title=[[Histories (Herodotus)|Histories]] |at=[https://www.perseus.tufts.edu/cgi-bin/ptext?lookup=Hdt.+3.115.1 3.115]}}</ref> The Carthaginian sailor [[Himilco]] is said to have visited the island in the 6th or 5th century BC and the Greek explorer [[Pytheas]] in the 4th. It was regarded as a place of mystery, with some writers refusing to believe it existed.<ref name="Plutarch">{{Citation |author=[[Plutarch]] |title=Life of Caesar |at=[https://penelope.uchicago.edu/Thayer/E/Roman/Texts/Plutarch/Lives/Caesar*.html#23.2 23.2]}}</ref>

The first direct Roman contact was when [[Julius Caesar]] undertook two expeditions in 55 and 54 BC, as part of his conquest of [[Gaul]], believing the Britons were helping the Gallic resistance. The first expedition was more a reconnaissance than a full invasion and gained a foothold on the coast of [[Kent]] but was unable to advance further because of storm damage to the ships and a lack of cavalry. Despite the military failure, it was a political success, with the [[Roman Senate]] declaring a 20-day public holiday in Rome to honour the unprecedented achievement of obtaining hostages from Britain and defeating [[Belgae|Belgic]] tribes on returning to the continent.<ref>{{Citation |last=Caesar |first=Julius |title=''Commentarii de Bello Gallico'' |at=[[s:Commentaries on the Gallic War/Book 4#20|IV 20–36]] |language=la}}</ref>

The second invasion involved a substantially larger force and Caesar coerced or invited many of the native Celtic tribes to pay tribute and give hostages in return for peace. A friendly local king, [[Mandubracius]], was installed, and his rival, [[Cassivellaunus]], was brought to terms. Hostages were taken, but historians disagree over whether any tribute was paid after Caesar returned to Gaul.<ref>{{Citation |last=Caesar |first=Julius |title=''Commentarii de Bello Gallico'' |at=[[s:Commentaries on the Gallic War/Book 5#8|V 8–23]] |language=la}}</ref>

Caesar conquered no territory and left no troops behind, but he established [[patronage in ancient Rome|clients]] and brought Britain into Rome's [[sphere of influence]]. [[Augustus]] planned invasions in 34, 27 and 25 BC, but circumstances were never favourable,<ref>{{Citation |last=Dio |first=Cassius |title=Historia Romana |trans-title=Roman History |at=[https://penelope.uchicago.edu/Thayer/E/Roman/Texts/Cassius_Dio/49*.html#38 49.38], [https://penelope.uchicago.edu/Thayer/E/Roman/Texts/Cassius_Dio/53*.html#22 53.22], [https://penelope.uchicago.edu/Thayer/E/Roman/Texts/Cassius_Dio/53*.html#25 53.25] |language=la}}</ref> and the relationship between Britain and Rome settled into one of diplomacy and trade. [[Strabo]], writing late in Augustus's reign, claimed that taxes on trade brought in more annual revenue than any conquest could.<ref>{{Citation |author=[[Strabo]] |title=[[Geographica]] |at=[https://penelope.uchicago.edu/Thayer/E/Roman/Texts/Strabo/4E*.html 4.5]}}</ref> Archaeology shows that there was an increase in imported luxury goods in southeastern Britain.<ref name="Branigan">{{Cite book |last=Branigan |first=Keith |title=Peoples of Roman Britain: The Catuvellauni |publisher=Sutton Publishing |year=1985 |isbn=978-0-8629-9255-2}}</ref> Strabo also mentions British kings who sent embassies to Augustus, and Augustus's own ''{{Lang|la|[[Res Gestae Divi Augusti|Res Gestae]]}}'' refers to two British kings he received as refugees.<ref>{{Citation |author=[[Augustus]] |title=[[Res Gestae Divi Augusti]] |trans-title=The Deeds of the Divine Augustus |at=[https://penelope.uchicago.edu/Thayer/E/Roman/Texts/Augustus/Res_Gestae/6*.html#32 32] |language=la}}</ref> When some of [[Tiberius]]'s ships were carried to Britain in a storm during his campaigns in [[Germania|Germany]] in 16 AD, they came back with tales of monsters.<ref>{{Citation |author=[[Tacitus]] |title=[[Annals (Tacitus)|Annals]] |at=[[s:The Annals (Tacitus)/Book 2#24|2.24]]}}</ref>

Rome appears to have encouraged a balance of power in southern Britain, supporting two powerful kingdoms: the [[Catuvellauni]], ruled by the descendants of [[Tasciovanus]], and the [[Atrebates]], ruled by the descendants of [[Commius]].<ref>{{Harvp|Creighton|2000}}.</ref> This policy was followed until 39 or 40 AD, when [[Caligula]] received an exiled member of the Catuvellaunian dynasty and planned an invasion of Britain that collapsed in farcical circumstances before it left Gaul.<ref>{{Citation |author=[[Suetonius]] |title=[[The Twelve Caesars#Caligula|Caligula]] |at=[https://penelope.uchicago.edu/Thayer/E/Roman/Texts/Suetonius/12Caesars/Caligula*.html#44 44–46]}}</ref><ref>{{Citation |last=Dio |first=Cassius |title=Historia Romana |at=[https://penelope.uchicago.edu/Thayer/E/Roman/Texts/Cassius_Dio/59*.html#25 59.25] |language=la}}</ref> When [[Claudius]] successfully invaded in 43 AD, it was in aid of another fugitive British ruler, [[Verica]] of the Atrebates.

=== Roman invasion ===
{{Main|Roman conquest of Britain}}

The invasion force in 43 AD was led by [[Aulus Plautius]],<ref>{{Citation |last=Dio |first=Cassius |title=Historia Romana |at=[https://penelope.uchicago.edu/Thayer/E/Roman/Texts/Cassius_Dio/60*.html#19 60.19–22] |language=la}}</ref> but it is unclear how many [[Roman legion|legions]] were sent. The ''{{Lang|la|[[Legio II Augusta]]}}'', commanded by future emperor [[Vespasian]], was the only one directly attested to have taken part.<ref>{{Citation |last=Tacitus |title=[[Histories (Tacitus)|Histories]] |at=[[s:The Histories (Tacitus)/Book 3#44|3.44]]}}</ref> The ''{{Lang|la|[[Legio IX Hispana]]}}'',<ref>{{Citation |last=Tacitus |title=Annals |at=[[s:The Annals (Tacitus)/Book 14#32|14.32]]}}</ref> the ''{{Lang|la|[[Legio XIV Gemina|XIV Gemina]]}}'' (later styled ''{{Lang|la|Martia Victrix}}'') and the ''{{Lang|la|[[Legio XX Valeria Victrix|XX]]}}'' (later styled ''{{Lang|la|Valeria Victrix}}'')<ref>{{Citation |last=Tacitus |title=Annals |at=[[s:The Annals (Tacitus)/Book 14#34|14.34]]}}</ref> are known to have served during the [[Boudican revolt]] of 60/61, and were probably there since the initial invasion. This is not certain because the [[Roman army]] was flexible, with units being moved around whenever necessary. The ''{{Lang|la|IX Hispana}}'' may have been permanently stationed, with records showing it at [[Eboracum]] ([[York]]) in 71 and on a building inscription there dated 108, before being destroyed in the east of the Empire, possibly during the [[Bar Kokhba revolt]].<ref name="Webster">{{Cite book |last=Webster |first=Graham |url=https://books.google.com/books?id=v0f4SEf7rosC&pg=PA66 |title=The Roman Imperial Army of the first and second centuries AD |publisher=University of Oklahoma Press |year=1998 |isbn=978-0-8061-3000-2 |edition=New ed of 3rd revised |page=66}}</ref>

The invasion was delayed by a troop mutiny until an imperial [[freedman]] persuaded them to overcome their fear of crossing the [[Oceanus|Ocean]] and campaigning beyond the limits of the known world. They sailed in three divisions, and probably landed at [[Richborough]] in [[Kent]]; at least part of the force may have landed near [[Fishbourne, West Sussex]].<ref>{{Harvp|Manley|2002}}.</ref>

[[File:British.coinage.Roman.invasion.jpg|thumb|left|Conquests under Aulus Plautius, focused on the commercially valuable southeast of Britain]]
The Catuvellauni and their allies were defeated in two battles: the first, assuming a Richborough landing, on the [[battle of the Medway|river Medway]], the second on the [[river Thames]]. One of their leaders, [[Togodumnus]], was killed, but his brother [[Caratacus]] survived to continue resistance elsewhere. Plautius halted at the Thames and sent for Claudius, who arrived with reinforcements, including artillery and elephants, for the final march to the Catuvellaunian capital, [[Camulodunum]] ([[Colchester]]). Vespasian subdued the southwest,<ref>{{Citation |last=Suetonius |title=[[The Twelve Caesars#Vespasian|Vespasian]] |at=[https://penelope.uchicago.edu/Thayer/E/Roman/Texts/Suetonius/12Caesars/Vespasian*.html#4 4]}}</ref> [[Tiberius Claudius Cogidubnus|Cogidubnus]] was set up as a friendly king of several territories,<ref>{{Citation |last=Tacitus |title=[[Agricola (book)|Agricola]] |at=[[:s:Agricola#14|14]]}}</ref> and treaties were made with tribes outside direct Roman control.

British archaeologist Richard Hingley said that the [[Roman conquest of Britain]], beginning with [[Julius Caesar]]'s expeditions and culminating with the construction of [[Hadrian's Wall]], was a drawn-out process rather than an inevitable or swift victory.<ref>{{Cite book |last=Hingley |first=Richard |title=Conquering the ocean: the Roman invasion of Britain |date=2022 |publisher=Oxford University Press |isbn=978-0-19-093741-6 |series=Ancient warfare and civilization |location=New York |pages=17–42 |quote=The conquest of this exotic island, however, was a challenge that even Caesar, despite his political and military brilliance, had been unable to achieve.}}</ref>

=== Establishment of Roman rule ===

{{Further|Romano-British culture}}
{{Gallery
|title  = Roman invasion of Britain
|align  = right
|width  = 180
|height = 180
|File:Roman.Britain.campaigns.43.to.60.jpg|Roman campaigns 43–60
|File:Agricola.Campaigns.80.84.jpg|Agricola's campaigns
}}
After capturing the south of the island, the Romans turned their attention to what is now [[Wales]]. The [[Silures]], [[Ordovices]] and [[Deceangli]] remained implacably opposed to the invaders and for the first few decades were the focus of Roman military attention, despite occasional minor revolts among Roman allies like the [[Brigantes]] and the [[Iceni]]. The Silures were led by [[Caratacus]], and he carried out an effective [[guerrilla warfare|guerrilla]] campaign against Governor [[Publius Ostorius Scapula]]. Finally, in 51, Ostorius lured Caratacus into a set-piece battle and [[Caratacus' last battle|defeated him]]. The British leader sought refuge among the Brigantes, but their queen, [[Cartimandua]], proved her loyalty by surrendering him to the Romans. He was brought as a captive to Rome, where a [[Caratacus#Captive in Rome|dignified speech]] he made during Claudius's triumph persuaded the emperor to spare his life. The Silures were still not pacified, and Cartimandua's ex-husband [[Venutius]] replaced Caratacus as the most prominent leader of British resistance.<ref>{{Citation |last=Tacitus |title=Annals |at=[https://www.perseus.tufts.edu/cgi-bin/ptext?lookup=Tac.+Ann.+12.31 12:31–38]}}</ref>

On [[Nero]]'s accession, Roman Britain extended as far north as [[Lindum Colonia|Lindum]]. [[Gaius Suetonius Paulinus]], the conqueror of [[Mauretania]] (modern day [[Algeria]] and [[Morocco]]), then became governor of Britain, and in 60 and 61 he moved against Mona ([[Anglesey]]) to settle accounts with [[Druid]]ism once and for all. Paulinus led his army across the [[Menai Strait]] and massacred the Druids and burnt their sacred groves.

While Paulinus was [[Roman conquest of Anglesey|campaigning in Mona]], the southeast of Britain rose in revolt under the leadership of [[Boudica]]. She was the widow of the recently deceased king of the Iceni, Prasutagus. The Roman historian Tacitus reports that Prasutagus had left a will leaving half his kingdom to Nero in the hope that the remainder would be left untouched. He was wrong. When his will was enforced, Rome{{Clarify|date=September 2023}}  responded by violently seizing the tribe's lands in full. Boudica protested. In consequence, Rome{{Clarify|date=September 2023}}  punished her and her daughters by flogging and rape. In response, the Iceni, joined by the [[Trinovantes]], destroyed the Roman colony at Camulodunum ([[Colchester]]) and [[Battle of Camulodunum|routed]] the part of the IXth Legion that was sent to relieve it. Paulinus rode to [[London]] (then called [[Londinium]]), the rebels' next target, but concluded it could not be defended. Abandoned, it was destroyed, as was [[Verulamium]] (St. Albans). Between seventy and eighty thousand people are said to have been killed in the three cities. But Paulinus regrouped with two of the three legions still available to him, chose a battlefield, and, despite being outnumbered by more than twenty to one, defeated the rebels in the [[Battle of Watling Street]]. Boudica died not long afterwards, by self-administered poison or by illness.<ref>{{Citation |last=Tacitus |title=Agricola |at=[[:s:Agricola#14|14.17]], [https://www.perseus.tufts.edu/cgi-bin/ptext?lookup=Tac.+Ann.+14.29 14.29–39]}}</ref><ref>{{Citation |last=Cassius Dio |title=Historia Romana |at=[https://penelope.uchicago.edu/Thayer/E/Roman/Texts/Cassius_Dio/62*.html#1 62.1–12] |language=la}}</ref> During this time, the Emperor Nero considered withdrawing Roman forces from Britain altogether.<ref>{{Citation |last=Suetonius |title=[[The Twelve Caesars#Nero|Nero]] |at=[https://penelope.uchicago.edu/Thayer/E/Roman/Texts/Suetonius/12Caesars/Nero*.html#18 18]}}</ref>

[[File:Templeborough Roman Fort visualised 3D flythrough - Rotherham.webm|thumb|left|[[Templeborough|Templeborough Roman fort]] in South Yorkshire. The reconstruction was created for Rotherham Museums and Galleries.]]

There was further turmoil in 69, the "[[Year of the Four Emperors]]". As civil war raged in Rome, weak governors were unable to control the legions in Britain, and Venutius of the Brigantes seized his chance. The Romans had previously defended Cartimandua against him, but this time were unable to do so. Cartimandua was evacuated, and Venutius was left in control of the north of the country. After Vespasian secured the empire, his first two appointments as governor, [[Quintus Petillius Cerialis]] and [[Frontinus|Sextus Julius Frontinus]], took on the task of subduing the Brigantes and Silures respectively.<ref>{{Citation |last=Tacitus |title=Agricola |at=[[:s:Agricola#16|16–17]] |language=la}}; {{Citation |last=Tacitus |title=[[Histories (Tacitus)|Histories]] |at=[[:s:The Histories (Tacitus)/Book 1#60|1.60]], [[:s:The Histories (Tacitus)/Book 3#45|3.45]]}}</ref> Frontinus extended Roman rule to all of [[South Wales]], and initiated exploitation of the mineral resources, such as the [[gold mining|gold mines]] at [[Dolaucothi Gold Mines|Dolaucothi]].

In the following years, the Romans conquered more of the island, increasing the size of Roman Britain. Governor [[Gnaeus Julius Agricola]], father-in-law to the historian [[Tacitus]], conquered the [[Ordovices]] in 78. With the ''{{Lang|la|XX Valeria Victrix}}'' legion, Agricola defeated the [[Caledonians]] in 84 at the [[Battle of Mons Graupius]], in north-east Scotland.<ref>{{Citation |last=Tacitus |title=Agricola |at=[[:s:Agricola#18|18.38]] |language=la}}</ref> This was the high-water mark of Roman territory in Britain: shortly after his victory, Agricola was recalled from Britain back to Rome and awarded the ornaments of a triumph, before returning to continue as governor. By 87 the decision was taken to abandon most of the land north of the [[Cheviot Hills]] allowing for troops to be moved to other frontiers which were under pressure. Tacitus reports Agricola as feeling bitter about this turn of events.<ref>{{cite odnb|id=48290|title=Julius Agricola, Gnaeus [known as Agricola] |last=Todd|first=Malcolm |year=2004 |ref=none}}</ref>

For much of the history of Roman Britain, a large number of soldiers were garrisoned on the island. This required that the emperor station a trusted senior man as governor of the province. As a result, many future emperors served as governors or legates in this province, including [[Vespasian]], [[Pertinax]], and [[Gordian I]].
{{Gallery
|title  = Roman military organisation in the north
|align  = right
|width  = 180
|height = 180
|File:Roman.Scotland.north.84.jpg|In 84 AD
|File:Roman.Scotland.north.155.jpg|In 155 AD
}}

=== Occupation of and retreat from southern Scotland ===
{{Anchor|Occupation and retreat from southern Scotland|reason=Old section name; may have incoming links.}}
{{Further|Scotland during the Roman Empire|Hadrian's Wall|Antonine Wall}}

There is no historical source describing the decades that followed Agricola's recall. Even the name of his replacement is unknown. Archaeology has shown that some [[Castra|Roman forts]] south of the Forth–Clyde isthmus were rebuilt and enlarged; others appear to have been abandoned. By 87 the frontier had been consolidated on the [[Stanegate]]. Roman coins and pottery have been found circulating at native settlement sites in the [[Scottish Lowlands]] in the years before 100, indicating growing [[Romanization (cultural)|Romanisation]]. Some of the most important sources for this era are the writing tablets from the fort at [[Vindolanda]] in [[Northumberland]], mostly dating to 90–110. These tablets provide evidence for the operation of a Roman fort at the edge of the Roman Empire, where officers' wives maintained polite society while merchants, hauliers and military personnel kept the fort operational and supplied.

Around 105 there appears to have been a serious setback at the hands of the tribes of the [[Picts]]: several Roman forts were destroyed by fire, with human remains and damaged [[armour]] at ''[[Trimontium (Newstead)|Trimontium]]'' (at modern [[Newstead, Scottish Borders|Newstead]], in SE Scotland) indicating hostilities at least at that site.{{Citation needed|date=March 2022}} There is also circumstantial evidence that auxiliary reinforcements were sent from Germany, and an unnamed British war of the period is mentioned on the gravestone of a [[tribune]] of [[Cyrene (mythology)|Cyrene]]. [[Trajan's Dacian Wars]] may have led to troop reductions in the area or even total withdrawal followed by slighting of the forts by the Picts rather than an unrecorded military defeat. The Romans were also in the habit of destroying their own forts during an orderly withdrawal, in order to deny resources to an enemy. In either case, the frontier probably moved south to the line of the [[Stanegate]] at the [[Solway Firth|Solway]]–[[River Tyne|Tyne]] isthmus around this time.

[[File:Hadrians Wall from Housesteads1.jpg|thumb|upright=1.05|left|[[Hadrian's Wall]] viewed looking east from [[Housesteads Roman Fort]] (Vercovicium)]]
[[File:Prima Europe tabula.jpg|thumb|upright=1.5|left|''Prima Europe tabula''. A 1486 [[woodcut]] copy of [[Ptolemy]]'s 2nd-century map of Roman Britain]]
A new crisis occurred at the beginning of [[Hadrian]]'s reign (117): a rising in the north which was suppressed by [[Quintus Pompeius Falco]]. When Hadrian reached Britannia on his famous tour of the Roman provinces around 120, he directed an extensive defensive wall, known to posterity as [[Hadrian's Wall]], to be built close to the line of the Stanegate frontier. Hadrian appointed [[Aulus Platorius Nepos]] as governor to undertake this work who brought the ''{{Lang|la|[[Legio VI Victrix]]}}'' legion with him from ''{{Lang|la|[[Germania Inferior]]}}''. This replaced the famous ''{{Lang|la|[[Legio IX Hispana]]}}'', whose disappearance has been much discussed. Archaeology indicates considerable political instability in Scotland during the first half of the 2nd century, and the shifting frontier at this time should be seen in this context.

In the reign of [[Antoninus Pius]] (138–161) the Hadrianic border was briefly extended north to the Forth–Clyde isthmus, where the [[Antonine Wall]] was built around 142 following the military reoccupation of the Scottish lowlands by a new governor, [[Quintus Lollius Urbicus]].

The first Antonine occupation of Scotland ended as a result of a further crisis in 155–157, when the [[Brigantes]] revolted. With limited options to despatch reinforcements, the Romans moved their troops south, and this rising was suppressed by Governor [[Gnaeus Julius Verus]]. Within a year the Antonine Wall was recaptured, but by 163 or 164 it was abandoned. The second occupation was probably connected with Antoninus's undertakings to protect the [[Votadini]] or his pride in enlarging the empire, since the retreat to the Hadrianic frontier occurred not long after his death when a more objective strategic assessment of the benefits of the Antonine Wall could be made. The Romans did not entirely withdraw from Scotland at this time: the large fort at Newstead was maintained along with seven smaller outposts until at least 180.

During the twenty-year period following the reversion of the frontier to Hadrian's Wall in 163/4, Rome was concerned with continental issues, primarily [[Marcomannic Wars|problems in the Danubian provinces]]. Increasing numbers of [[hoard]]s of buried coins in Britain at this time indicate that peace was not entirely achieved. Sufficient Roman silver has been found in Scotland to suggest more than ordinary trade, and it is likely that the Romans were reinforcing treaty agreements by paying tribute to their implacable enemies, the [[Picts]].

In 175, a large force of [[Sarmatians|Sarmatian]] cavalry, consisting of 5,500 men, arrived in Britannia, probably to reinforce troops fighting unrecorded uprisings. In 180, Hadrian's Wall was breached by the Picts and the commanding officer or governor was killed there in what [[Cassius Dio]] described as the most serious war of the reign of [[Commodus]]. [[Ulpius Marcellus]] was sent as replacement governor and by 184 he had won a new peace, only to be faced with a mutiny from his own troops. Unhappy with Marcellus's strictness, they tried to elect a legate named [[Caerellius Priscus|Priscus]] as usurper governor; he refused, but Marcellus was lucky to leave the province alive. The Roman army in Britannia continued its insubordination: they sent a delegation of 1,500 to Rome to demand the execution of [[Tigidius Perennis]], a [[Praetorian prefect]] who they felt had earlier wronged them by posting lowly [[equites]] to legate ranks in Britannia. Commodus met the party outside Rome and agreed to have Perennis killed, but this only made them feel more secure in their mutiny.

The future emperor [[Pertinax]] (lived 126–193) was sent to Britannia to quell the mutiny and was initially successful in regaining control, but a riot broke out among the troops. Pertinax was attacked and left for dead, and asked to be recalled to Rome, where he briefly succeeded [[Commodus]] as emperor in 192.

=== Third century ===
The death of Commodus put into motion a series of events which eventually led to civil war. Following the short reign of Pertinax, several rivals for the emperorship emerged, including [[Septimius Severus]] and [[Clodius Albinus]]. The latter was the new governor of Britannia, and had seemingly won the natives over after their earlier rebellions; he also controlled three legions, making him a potentially significant claimant. His sometime rival Severus promised him the title of [[Caesar (title)|Caesar]] in return for Albinus's support against [[Pescennius Niger]] in the east. Once Niger was neutralised, Severus turned on his ally in Britannia; it is likely that Albinus saw he would be the next target and was already preparing for war.

Albinus crossed to [[Gaul]] in 195, where the provinces were also sympathetic to him, and set up at [[Lugdunum]]. Severus arrived in February 196, and the ensuing battle was decisive. Albinus came close to victory, but Severus's reinforcements won the day, and the British governor committed suicide. Severus soon purged Albinus's sympathisers and perhaps confiscated large tracts of land in Britain as punishment. Albinus had demonstrated the major problem posed by Roman Britain. In order to maintain security, the province required the presence of three legions, but command of these forces provided an ideal power base for ambitious rivals. Deploying those legions elsewhere would strip the island of its garrison, leaving the province defenceless against uprisings by the native Celtic tribes and against invasion by the [[Picts]] and [[Gaels|Scots]].

The traditional view is that northern Britain descended into anarchy during Albinus's absence. Cassius Dio records that the new Governor, [[Virius Lupus]], was obliged to buy peace from a fractious northern tribe known as the [[Maeatae]]. The succession of militarily distinguished governors who were subsequently appointed suggests that enemies of Rome were posing a difficult challenge, and [[Lucius Alfenus Senecio]]'s report to Rome in 207 describes barbarians "rebelling, over-running the land, taking loot and creating destruction". In order to rebel, of course, one must be a subject – the Maeatae clearly did not consider themselves such. Senecio requested either reinforcements or an Imperial expedition, and Severus chose the latter, despite being 62 years old. Archaeological evidence shows that Senecio had been rebuilding the defences of Hadrian's Wall and the forts beyond it, and Severus's arrival in Britain prompted the enemy tribes to sue for peace immediately. The emperor had not come all that way to leave without a victory, and it is likely that he wished to provide his teenage sons [[Caracalla]] and [[Publius Septimius Geta|Geta]] with first-hand experience of controlling a hostile barbarian land.
[[File:Roman.Britain.Severan.Campaigns.jpg|thumb|Northern campaigns, 208–211]]
An [[Roman invasion of Caledonia 208–210|invasion of Caledonia]] led by Severus and probably numbering around 20,000 troops moved north in 208 or 209, crossing the Wall and passing through eastern Scotland on a route similar to that used by Agricola. Harried by punishing guerrilla raids by the northern tribes and slowed by an unforgiving terrain, Severus was unable to meet the Caledonians on a battlefield. The emperor's forces pushed north as far as the [[River Tay]], but little appears to have been achieved by the invasion, as peace treaties were signed with the Caledonians. By 210 Severus had returned to York, and the frontier had once again become Hadrian's Wall. He assumed the title ''{{Lang|la|Britannicus}}'' but the title meant little with regard to the unconquered north, which clearly remained outside the authority of the Empire. Almost immediately, another northern tribe, the Maeatae, went to war. Caracalla left with a [[punitive expedition]], but by the following year his ailing father had died and he and his brother left the province to press their claim to the throne.

As one of his last acts, Severus tried to solve the problem of powerful and rebellious governors in Britain by dividing the province into ''{{Lang|la|[[Britannia Superior]]}}'' and ''{{Lang|la|[[Britannia Inferior]]}}''. This kept the potential for rebellion in check for almost a century. Historical sources provide little information on the following decades, a period known as the Long Peace. Even so, the number of buried hoards found from this period rises, suggesting continuing unrest. A string of forts were built along the coast of southern Britain to control piracy; and over the following hundred years they increased in number, becoming the [[Saxon Shore|Saxon Shore Forts]].

During the middle of the 3rd century, the Roman Empire was convulsed by barbarian invasions, rebellions and new imperial pretenders. Britannia apparently avoided these troubles, but increasing [[inflation]] had its economic effect. In 259 a so-called [[Gallic Empire]] was established when [[Postumus]] rebelled against [[Gallienus]]. Britannia was part of this until 274 when [[Aurelian]] reunited the empire.

Around the year 280, a half-[[Romano-Britons|British]] officer named [[Bonosus (usurper)|Bonosus]] was in command of the Romans' [[Classis Germanica|Rhenish fleet]] when the [[Germania|Germans]] managed to burn it at anchor. To avoid punishment, he [[Roman usurper|proclaimed himself emperor]] at [[Colonia Agrippina]] ([[Cologne]]) but was crushed by [[Marcus Aurelius Probus]]. Soon afterwards, an unnamed [[governors of Roman Britain|governor]] of one of the British provinces also attempted an uprising. Probus put it down by sending irregular troops of [[Vandals]] and [[Burgundians]] across the Channel.

The [[Carausian Revolt]] led to a short-lived [[Britannic Empire]] from 286 to 296. [[Carausius]] was a [[Menapii|Menapian]] [[Roman navy|naval]] commander of the [[Classis Britannica|Britannic fleet]]; he revolted upon learning of a death sentence ordered by the emperor [[Maximian]] on charges of having abetted [[Franks|Frankish]] and [[Saxon people|Saxon]] [[Roman piracy|pirates]] and having embezzled recovered treasure. He consolidated control over all the provinces of Britain and some of northern Gaul while Maximian dealt with other uprisings. An invasion in 288 failed to unseat him and an uneasy peace ensued, with Carausius issuing coins and inviting official recognition. In 293, the [[caesar (title)|junior emperor]] [[Constantius Chlorus]] launched a second offensive, besieging the rebel port of [[Gesoriacum]] ([[Boulogne-sur-Mer]]) by land and sea. After it fell, Constantius attacked Carausius's other Gallic holdings and Frankish allies and Carausius was usurped by his treasurer, [[Allectus]]. [[Julius Asclepiodotus]] landed an invasion fleet near [[Southampton]] and defeated Allectus in a land battle.<ref>{{Citation |last=Anonymous |title=[[Panegyrici Latini]] |at=VIII.10}}; {{Cite book |author=[[Aurelius Victor]] |title=Liber de Caesaribus |at=[http://www.thelatinlibrary.com/victor.caes.html#39 39] |language=la |trans-title=Book of Caesars}}; {{Cite book |author=[[Eutropius (historian)|Eutropius]] |title=Breviarium historiae Romanae |at={{usurped|1=[https://web.archive.org/web/20031222152525/http://www.forumromanum.org/literature/eutropius/trans9.html#21 21–22]}} |language=la |trans-title=Abridgement of Roman History}}; {{Citation |author=[[Orosius]] |title=Historiae Adversus Paganos |trans-title=Seven Books of History Against the Pagans |at=[http://www.attalus.org/latin/orosius7A.html#25 7.25] |language=la}}</ref>

=== Fourth century government ===
{{Main|Britannia I|Britannia II|Flavia Caesariensis|Maxima Caesariensis|Valentia (Roman province)}}
[[File:Roman Britain 410.jpg|right|upright=0.9|thumb|One possible arrangement of the late Roman provinces, with [[Valentia (Roman Britain)|Valentia]] between the walls]]
[[File:Roman Britain - AD 400.png|right|upright=0.9|thumb|Another possible arrangement, with other possible placements of [[Valentia (Roman province)|Valentia]] noted]]

In a reform carried out by 312, the Diocese of Britain was divided into four provinces, ''Maxima Caesariensis'', ''Flavia Caesariensis'', ''Britannia Prima'' and ''Britannia Secunda''. The [[Roman diocese|diocese]] was governed by a ''[[vicarius]]'', and Britain was part of the Gallic region under the overall authority of a [[praetorian prefect]], based at [[Trier]].{{sfn|Mattingly|2006|p=227}}

The ''vicarius'' was based at Londinium as the principal city of the diocese.<ref>{{cite web |last1=Stillwell |first1=Richard |last2=MacDonald |first2= William L. |last3=McAllister |first3=Marian Holland |title=The Princeton Encyclopedia of Classical Sites |url=http://www.perseus.tufts.edu/hopper/text?doc=Perseus:text:1999.04.0006:entry=londinium |website=perseus.tufts.edu |access-date=18 July 2023}}</ref> Londinium and Eboracum continued as provincial capitals and the territory was divided up into smaller provinces for administrative efficiency.

Civilian and military authority of a province was no longer exercised by one official, and the governor was stripped of military command, which was handed over to the ''[[Dux Britanniarum]]'' by 314. The governor of a province assumed more financial duties (the procurators of the Treasury ministry were slowly phased out in the first three decades of the 4th century). The Dux was commander of the troops of the Northern Region, primarily along Hadrian's Wall, and his responsibilities included protection of the frontier. He had significant autonomy due in part to the distance from his superiors.<ref>Collins, Rob. Hadrian's Wall and the End of Empire, Routledge, 2012 ISBN 9780415884112</ref>

The tasks of the ''vicarius'' were to control and coordinate the activities of governors; monitor but not interfere with the daily functioning of the Treasury and Crown Estates, which had their own administrative infrastructure; and act as the regional quartermaster-general of the armed forces. In short, as the sole civilian official with superior authority, he had general oversight of the administration, as well as direct control, while not absolute, over governors who were part of the prefecture; the other two fiscal departments were not.

The early-4th-century [[Verona List]], the late-4th-century work of [[Sextus Rufus]], and the early-5th-century [[Notitia Dignitatum|List of Offices]] and work of [[Polemius Silvius]] all list four provinces by some variation of the names [[Britannia Prima|Britannia I]], [[Britannia Secunda|Britannia II]], [[Maxima Caesariensis]], and [[Flavia Caesariensis]]; all of these seem to have initially been directed by a [[governors of Roman Britain|governor]] (''[[praeses]]'') of [[equestrian (Roman)|equestrian]] rank. The 5th-century sources list a fifth province named [[Valentia (Roman Britain)|Valentia]] and give its governor and Maxima's a [[Roman consul|consular]] rank.{{Efn|The [[Verona List]] actually includes a note that the Diocese of the Britains had ''six'' provinces, but then lists four. [[Sextus Rufus]] listed six provinces, including the highly dubious "province of Orcades" ([[Orkney Islands]]). Some scholars{{Who|date=February 2015}} argue that the initial reforms established three provinces: Britannia&nbsp;I, Britannia&nbsp;II, and Britannia Caesariensis, which was subsequently divided into Flavia and Maxima.}} [[Ammianus Marcellinus|Ammianus]] mentions Valentia as well, describing its creation by [[Count Theodosius]] in 369 after the quelling of the [[Great Conspiracy]]. Ammianus considered it a re-creation of a formerly lost province,<ref>[[Ammianus Marcellinus]]. ''Rerum gestarum Libri XXXI'' [''31 Books of Deeds'']. {{Abbr|a.|Before}}&nbsp;391&nbsp;AD. {{In lang|la}} Translated by [[Charles Duke Yonge|Charles Yonge]]. [[s:Roman History/Book XXVIII#III|''Roman History'', Vol.&nbsp;XXVIII, Ch.&nbsp;III]]. Bohn (London), 1862. Hosted at [[s:Main Page|Wikisource]].</ref> leading some to think there had been an earlier fifth province under another name (may be the enigmatic "Vespasiana"?<ref>{{Cite web |date=9 December 2019 |title=A R O S: VESPASIANA: A PROVINCE OF ROMAN BRITANNIA? |url=https://adviceandresearch.blogspot.com/2019/12/vespasiana-province-of-roman-britannia.html}}</ref>), and leading others to place Valentia beyond [[Hadrian's Wall]], in the territory abandoned south of the [[Antonine Wall]].

Reconstructions of the provinces and provincial capitals during this period partially rely on [[Celtic Christianity|ecclesiastical]] records. On the assumption that the early bishoprics mimicked the imperial hierarchy, scholars use the list of bishops for the [[Council of Arles (314)|314 Council of Arles]]. The list is patently corrupt: the British delegation is given as including a [[Eborius|Bishop "Eborius"]] of [[Eboracum]] and two bishops "from [[Londinium]]" (one ''{{Lang|la|de civitate Londinensi}}'' and the other ''{{Lang|la|de civitate colonia Londinensium}}'').{{Efn |"Nomina Episcoporum, cum Clericis Suis, Quinam, et ex Quibus Provinciis, ad Arelatensem Synodum Convenerint" ["The Names of the Bishops with Their Clerics who Came Together at the Synod of Arles and from which Province They Came"] from the ''Consilia''<ref>[[Labbé, Philippe]] & [[Gabriel Cossart]] (eds.) [https://download.digitale-sammlungen.de/BOOKS/pdf_download.pl?id=bsb10321964 ''Sacrosancta Concilia ad Regiam Editionem Exacta: quae Nunc Quarta Parte Prodit Actior'' &#91;''The Sancrosanct Councils Exacted for the Royal Edition: which the Editors Now Produce in Four Parts''&#93;, Vol.&nbsp;I: "Ab Initiis Æræ Christianæ ad Annum CCCXXIV" &#91;"From the Beginning of the Christian Era to the Year 324"&#93;, col.&nbsp;1429.] The Typographical Society for Ecclesiastical Books (Paris), 1671.</ref> in [[Francis Thackery|Thackery]]<ref name=thacky/> {{In lang|la}}}} The error is variously emended: [[Bishop Ussher]] proposed ''[[Colonia Victricensis|Colonia]]'',<ref>Usserius, Jacobus &#91;[[James Ussher]]&#93;. ''Britannicarum Ecclesiarum Antiquitates, Quibus Inserta Est Pestiferæ adversus Dei Gratiam a Pelagio Britanno in Ecclesiam Inductæ Hæreseos Historia'' [''Antiquities of the Britannic Churches, into Which Is Inserted a History of the Pestilent Heretics Introduced against the Grace of God by Pelagius the Briton into the Church''], Vol.&nbsp;I., Ch.&nbsp;VIII, (Dublin), 1639. Reprinted as [https://archive.org/stream/wholeworkswithli05usshuoft#page/236/mode/2up ''The Whole Works of the Most Rev.&nbsp;James Ussher, D.&nbsp;D. Lord Archbishop of Armagh, and Primate of All Ireland'', Vol.&nbsp;V, Ch.&nbsp;VIII, p.&nbsp;236]. Hodges, Smith, &&nbsp;Co. (Dublin), 1864. {{In lang|la}}</ref> [[John Selden|Selden]] ''Col.'' or ''[[Colonia Camaloduni|Colon. Camalodun.]]'',<ref>Eutychius Ægyptius &#91;[[Eutychius the Egyptian]]&#93;. Edited, translated, & with commentary by Ioannes Seldenus &#91;[[John Selden]]&#93;. [https://books.google.com/books?id=u4xaAAAAQAAJ&pg=PA118 ''Ecclesiæ suæ Origines'' &#91;''Origins of His Church''&#93;, p.&nbsp;118.] R.&nbsp;& T.&nbsp;Whitaker for Richard Bishop (London), 1642. {{In lang|la}}</ref> and [[Henry Spelman|Spelman]] ''[[Colonia Cameloduni]]''<ref>Henricus Spelman &#91;[[Henry Spelman]]&#93; [https://books.google.com/books?id=SGlNAAAAcAAJ&pg=PA639 ''Concilia, Decreta, Leges, Constitutiones, in Re Ecclesiarum Orbis Britannici. ''Viz.'' Pambritannica, Pananglica, Scotica, Hibernica, Cambrica, Mannica, Provincialia, Dioecesana. Ab initio Christianæ ibidem Religionis, ad nostram usque ætatem'' &#91;''Councils, Decrees, Laws, Constitutions, Regarding the Churches of the Britannic Sphere. To wit, Great Britain, England, Scotland, Ireland, Wales, Man, Provincial, Diocesan. From the start of the Christian Religion there to our very age''&#93;, Vol.&nbsp;I, Index, p.&nbsp;639.] Richard Badger (London), 1639. {{In lang|la}}</ref> (all various names of [[Colchester]]);{{Efn |Although Ussher refers the reader to his earlier discussion of the [[28 Cities of Britain]], which notes that "Cair Colun" may refer to either Colchester in Essex or to a settlement in [[Merionethshire]].<ref>Usserius, Vol.&nbsp;I, Ch. V, reprinted as Ussher, Vol.&nbsp;V, [https://archive.org/stream/wholeworkswithli05usshuoft#page/82/mode/2up p.&nbsp;82.] {{In lang|la}}</ref>}} [[Thomas Gale|Gale]]<ref name="giter">Gale, Thomæ &#91;[[Thomas Gale]]&#93;. [https://archive.org/stream/antoniniiterbri00galegoog#page/n124/mode/2up ''Antonini Iter Britanniarum'' &#91;''Antoninus's Route of the Britains''&#93;, "Iter V. A Londinio Lugvvallium Ad Vallum" &#91;Route 5: From Londinium to Luguvalium at the Wall&#93;, p.&nbsp;96.] Published posthumously & edited by [[Roger Gale (antiquary)|R.&nbsp;Gale]]. M.&nbsp;Atkins (London), 1709. {{In lang|la}}</ref> and [[Joseph Bingham|Bingham]]<ref>[[Bingham, Joseph]]. ''[https://archive.org/stream/bub_gb_4rL7herLUK8C#page/n453/mode/2up Origines Ecclesiasticæ: The Antiquities of the Christian Church. With Two Sermons and Two Letters on the Nature and Necessity of Absolution. Reprinted from the Original Edition, MDCCVIII–MDCCXXII With an Enlarged Analytical Index.]'' Vol.&nbsp;I, Book&nbsp;IX, Ch.&nbsp;VI, §20: "Of the British church in England and Wales", p.&nbsp;396. Henry G. Bohn (London), 1856.</ref> offered ''{{Lang|la|[[colonia Lindi]]}}''<!--sic--> and [[Robert Henry (minister)|Henry]]<ref>Henry, Robert. [https://archive.org/stream/historyofgreat01henr#page/142/mode/2up ''The History of Great Britain, from the First Invasion of It by the Romans under Julius Cæsar. Written on a New Plan'', 2nd&nbsp;ed., Vol.&nbsp;I, Ch.&nbsp;2, s2, p.&nbsp;143.] 1st&nbsp;ed. published by T.&nbsp;Cadell (London), 1771. Reprinted by P.&nbsp;Byrne & J.&nbsp;Jones (Dublin), 1789.</ref> ''{{Lang|la|[[Colonia Lindum]]}}'' (both [[Lincoln, England|Lincoln]]); and [[Edward Stillingfleet|Bishop Stillingfleet]]<ref>[[Stillingfleet, Edward]]. [https://books.google.com/books?id=aRw1AQAAIAAJ&pg=PA77 ''Origines Britannicæ: or, the Antiquities of the British Churches with a Preface, concerning Some Pretended Antiquities Relating to Britain, in Vindication of the Bishop of St.&nbsp;Asaph'', New Ed., pp.&nbsp;77&nbsp;ff.] Wm.&nbsp;Straker (London), 1840.</ref> and [[Francis Thackeray]] read it as a [[scribal error]] of ''Civ. Col. Londin.'' for an original ''[[Colonia Legionis II|Civ. Col. Leg. II]]'' ([[Caerleon]]).<ref name="thacky">Thackery, Francis. [https://books.google.com/books?id=ZtgDAAAAQAAJ&pg=PA272 ''Researches into the Ecclesiastical and Political State of Ancient Britain under the Roman Emperors: with Observations upon the Principal Events and Characters Connected with the Christian Religion, during the First Five Centuries'', pp.&nbsp;272&nbsp;ff.] T.&nbsp;Cadell (London), 1843.</ref> On the basis of the Verona List, the priest and deacon who accompanied the bishops in some manuscripts are ascribed to the fourth province.

In the 12th century, [[Gerald of Wales]] described the supposedly [[metropolitan bishop|metropolitan sees]] of the [[Celtic Christianity|early British church]] established by the legendary [[list of Welsh saints|SS]]&nbsp;[[Saint Fagan|Fagan]] and "[[Saint Duvian|Duvian]]". He placed [[Britannia Prima]] in [[Wales]] and western England with its capital at "[[Isca Augusta|Urbs Legionum]]" ([[Caerleon]]); [[Britannia Secunda]] in [[Kent]] and southern England with its capital at "[[Dorobernia]]" ([[Canterbury]]); [[Flavia Caesariensis|Flavia]] in [[Mercia]] and central England with its capital at "[[Londinium|Lundonia]]" ([[City of London|London]]); "[[Maxima Caesariensis|Maximia]]" in northern England with its capital at [[Eboracum]] ([[York]]); and [[Valentia (Roman Britain)|Valentia]] in "[[Alba]]nia which is now [[Scotland]]" with its capital at [[St Andrews|St&nbsp;Andrews]].<ref name="letter">Giraldus Cambriensis [Gerald of Wales]. {{Cite web |year=1877 |title=''De Inuectionibus'' [On Invectives], Vol.&nbsp;II, Ch.&nbsp;I, in ''Y Cymmrodor: The Magazine of the Honourable Society of Cymmrodorion'', Vol.&nbsp;XXX, pp.&nbsp;130–1. |url=https://archive.org/stream/ycymmrodor30cymmuoft#page/130/mode/2up}} George Simpson &&nbsp;Co. (Devizes), 1920. {{In lang|la}}; [[Gerald of Wales]]. Translated by [[W.S. Davies]] as [https://archive.org/stream/ycymmrodor30cymmuoft#page/16/mode/2up ''The Book of Invectives of Giraldus Cambrensis'' in ''Y Cymmrodor: The Magazine of the Honourable Society of Cymmrodorion'', Vol.&nbsp;XXX, p.&nbsp;16.] George Simpson &&nbsp;Co. (Devizes), 1920.</ref> Modern scholars generally dispute the last: some place Valentia at or beyond [[Hadrian's Wall]] but St&nbsp;Andrews is beyond even the [[Antonine Wall]] and Gerald seems to have simply been supporting the antiquity of its church for political reasons.

A common modern reconstruction places the consular province of Maxima at Londinium, on the basis of its status as the seat of the diocesan ''vicarius''; places Prima in the west according to Gerald's traditional account but moves its capital to [[Corinium Dobunnorum|Corinium]] of the [[Dobunni]] ([[Cirencester]]) on the basis of an artifact recovered there referring to Lucius Septimius, a provincial [[rector (politics)|rector]]; places Flavia north of Maxima, with its capital placed at [[Lindum Colonia]] ([[Lincoln, England|Lincoln]]) to match one emendation of the bishops list from Arles;{{Efn |[[Bede]] also references a ''{{Lang|la|Provincia Lindisi}}'' or ''{{Lang|la|prouinciae Lindissi}}'', which was a later Saxon territory at the time of the [[Gregorian mission]].<ref>[[Beda Venerabilis]] [The Venerable Bede]. [[s:la:Historia Ecclesiastica gentis Anglorum - Liber Secundus#16|''Historia Ecclesiastica Gentis Anglorum'' &#91;The Ecclesiastical History of the English People&#93;, Vol.&nbsp;II, Ch.&nbsp;XVI]]. 731. Hosted at [[:s:la:Main Page|Latin Wikisource]]. {{In lang|la}}; Bede. Translated by [[Lionel Cecil Jane]] as [[s:Ecclesiastical History of the English People/Book 2#16|''The Ecclesiastical History of the English Nation'', Vol.&nbsp;2, Ch.&nbsp;16]]. J.M.&nbsp;Dent &&nbsp;Co. (London), 1903. Hosted at [[s:Main Page|Wikisource]].</ref>}} and places Secunda in the north with its capital at Eboracum (York). Valentia is placed variously in northern Wales around [[Deva Victrix|Deva]] ([[Chester]]); beside [[Hadrian's Wall]] around [[Luguvalium]] ([[Carlisle, England|Carlisle]]); and between the walls along [[Dere Street]].

=== Fourth century history ===
{{See also|Great Conspiracy}}
[[File:Roman.Britain.towns.villas.jpg|thumb|300px|4th century Roman towns and villas]]
[[File:Britain.4th.century.Roman.infrastructure.jpg|thumb|300px|4th century: Degree of Romanisation]]

Emperor Constantius returned to Britain in 306, despite his poor health, with an army aiming to invade northern Britain, the provincial defences having been rebuilt in the preceding years. Little is known of his campaigns with scant archaeological evidence, but fragmentary historical sources suggest he reached the far north of Britain and won a major battle in early summer before returning south. His son Constantine (later [[Constantine the Great]]) spent a year in northern Britain at his father's side, campaigning against the [[Picts]] beyond [[Hadrian's Wall]] in the summer and autumn.<ref>Barnes, ''Constantine and Eusebius'', 27, 298; Elliott, ''Christianity of Constantine'', 39; Odahl, 77–78, 309; Pohlsander, ''Emperor Constantine'', 15–16.; Mattingly, 233–234; {{Harvp|Southern|2012|pages=170, 341}}.</ref> Constantius died in [[York]] in July 306 with his son at his side. Constantine then successfully used Britain as the starting point of his march to the imperial throne, unlike the earlier usurper, Albinus.

In the middle of the century, the province was loyal for a few years to the usurper [[Magnentius]], who succeeded [[Constans]] following the latter's death. After the defeat and death of Magnentius in the [[Battle of Mons Seleucus]] in 353, [[Constantius II]] dispatched his chief imperial notary [[Paulus Catena]] to Britain to hunt down Magnentius's supporters. The investigation deteriorated into a [[witch-hunt]], which forced the ''{{Lang|la|vicarius}}'' [[Flavius Martinus]] to intervene. When Paulus retaliated by accusing Martinus of treason, the ''{{Lang|la|vicarius}}'' attacked Paulus with a sword, with the aim of assassinating him, but in the end he committed suicide.

As the 4th century progressed, there were increasing attacks from the [[Saxons]] in the east and the [[Scoti]] (Irish) in the west. A series of forts had been built, starting around 280, to defend the coasts, but these preparations were not enough when, in 367, a general assault of Saxons, [[Picts]], Scoti and [[Attacotti]], combined with apparent dissension in the garrison on Hadrian's Wall, left Roman Britain prostrate. The invaders overwhelmed the entire western and northern regions of Britannia and the cities were sacked.<ref>{{Cite book |last=Hughes |first=Ian |title=Imperial Brothers: Valentinian, Valens and the Disaster at Adrianople |date=2013 |publisher=Pen & Sword Military |isbn=978-1-8488-4417-9 |page=59}}</ref> This crisis, sometimes called the Barbarian Conspiracy or the [[Great Conspiracy]], was settled by [[Count Theodosius]] from 368 with a string of military and civil reforms. Theodosius crossed from Bononia ([[Boulogne-sur-Mer]]) and marched on Londinium where he began to deal with the invaders and made his base.<ref>Ammianus Marcellinus, Res Gestae 27.8.6</ref> An amnesty was promised to deserters which enabled Theodosius to regarrison abandoned forts. By the end of the year Hadrian's Wall was retaken and order returned. Considerable reorganization was undertaken in Britain, including the creation of a new province named Valentia, probably to better address the state of the far north. A new [[Dux Britanniarum]] was appointed, Dulcitius, with Civilis to head a new civilian administration.

Another imperial usurper, [[Magnus Maximus]], raised the standard of revolt at [[Segontium]] ([[Caernarfon]]) in north Wales in 383, and crossed the [[English Channel]]. Maximus held much of the western empire, and fought a successful campaign against the [[Picts]] and [[Scoti|Scots]] around 384. His continental exploits required troops from Britain, and it appears that forts at Chester and elsewhere were abandoned in this period, triggering raids and settlement in north Wales by the Irish. His rule was ended in 388, but not all the British troops may have returned: the Empire's military resources were stretched to the limit along the Rhine and Danube.
Around 396 there were more barbarian incursions into Britain. [[Stilicho]] led a punitive expedition.
It seems peace was restored by 399, and it is likely that no further garrisoning was ordered; by 401 more troops were withdrawn, to assist in the war against [[Alaric I]].

=== End of Roman rule ===

{{Main|End of Roman rule in Britain}}
[[File:Brittain 410.jpg|thumb|Roman Britain in 410]]

The traditional view of historians, informed by the work of [[Michael Rostovtzeff]], was of a widespread economic decline at the beginning of the 5th century. Consistent archaeological evidence has told another story, and the accepted view is undergoing re-evaluation. Some features are agreed: more opulent but fewer urban houses, an end to new public building and some abandonment of existing ones, with the exception of defensive structures, and the widespread formation of "[[dark earth]]" deposits indicating increased horticulture within urban precincts.<ref>Archaeological evidence of late 4th-century urban collapse is analysed by {{Cite book |last=Cleary |first=Simon Esmonde |title=The Ending of Roman Britain |date=2000}}; the "de-romanisation" of Britain is the subject of several accounts by [[Richard Reece]], including "Town and country: the end of Roman Britain", ''World Archaeology'' '''12''' (1980:77–92) and "The end of the city in Roman Britain", in {{Cite book |editor-first=J. |editor-last=Rich |title=The City in Antiquity |date=1992 |pages=136–144}}; {{Harvp|Loseby|2000|page=326f}} makes a strong case for discontinuity of urban life.</ref> Turning over the [[basilica]] at [[Silchester]] to industrial uses in the late 3rd century, doubtless officially condoned, marks an early stage in the de-urbanisation of Roman Britain.<ref name="Fulford">{{Cite journal |last=Fulford |first=Michael |author-link=Michael Fulford |date=1985 |title=Excavations... |journal=Antiquaries |volume=65 |pages=39–81 |doi=10.1017/S0003581500024690 |s2cid=164170447}}, noted in {{Harvp|Loseby|2000}}.</ref>

The abandonment of some sites is now believed to be later than had been thought. Many buildings changed use but were not destroyed. There was a growing number of barbarian attacks, but these targeted vulnerable rural settlements rather than towns. Some villas such as [[Chedworth Roman Villa|Chedworth]], [[Great Casterton]] in [[Rutland]] and [[Hucclecote]] in [[Gloucestershire]] had new mosaic floors laid around this time, suggesting that economic problems may have been limited and patchy. Many suffered some decay before being abandoned in the 5th century; the story of [[Saint Patrick]] indicates that villas were still occupied until at least 430. Exceptionally, new buildings were still going up in this period in [[Verulamium]] and [[Cirencester]]. Some urban centres, for example [[Canterbury]], [[Cirencester]], [[Wroxeter]], [[Winchester]] and [[Gloucester]], remained active during the 5th and 6th centuries, surrounded by large farming estates.

Urban life had generally grown less intense by the fourth quarter of the 4th century, and coins minted between 378 and 388 are very rare, indicating a likely combination of economic decline, diminishing numbers of troops, problems with the payment of soldiers and officials or with unstable conditions during the usurpation of Magnus Maximus 383–87. Coinage circulation increased during the 390s, but never attained the levels of earlier decades. Copper coins are very rare after 402, though minted silver and gold coins from hoards indicate they were still present in the province even if they were not being spent. By 407 there were very few new Roman coins going into circulation, and by 430 it is likely that coinage as a medium of exchange had been abandoned. Mass-produced wheel thrown pottery ended at approximately the same time; the rich continued to use metal and glass vessels, while the poor made do with humble "grey ware" or resorted to leather or wooden containers.

=== Sub-Roman Britain ===
{{Main|Sub-Roman Britain}}
[[File:End.of.Roman.rule.in.Britain.383.410.jpg|thumb|[[End of Roman rule in Britain]], 383–410]]
Towards the end of the 4th century Roman rule in Britain came under increasing pressure from [[barbarian]] attacks. Apparently, there were not enough troops to mount an effective defence. After elevating two disappointing [[Roman usurper|usurpers]], the army chose a soldier, [[Constantine III (Western Roman Emperor)|Constantine III]], to become emperor in 407. He crossed to Gaul but was defeated by [[Honorius (emperor)|Honorius]]; it is unclear how many troops remained or ever returned, or whether a commander-in-chief in Britain was ever reappointed. A [[Saxons|Saxon]] incursion in 408 was apparently repelled by the [[Britons (Celtic people)|Britons]], and in 409 [[Zosimus (historian)|Zosimus]] records that the natives expelled the Roman civilian administration. Zosimus may be referring to the [[Bagaudae]] rebellion of the [[Bretons|Breton]] inhabitants of [[Armorica]] since he describes how, in the aftermath of the revolt, all of Armorica and the rest of Gaul followed the example of the Brettaniai. A letter from Emperor Honorius in 410 has traditionally been seen as rejecting a British appeal for help, but it may have been addressed to [[Calabria|Bruttium]] or [[Bologna]].<ref name="Moorhead">{{Harvp|Moorhead|Stuttard|2012|page=[https://archive.org/details/romanswhoshapedb0000moor/page/238 238]}}.</ref> With the imperial layers of the military and civil government gone, administration and justice fell to municipal authorities, and local warlords gradually emerged all over Britain, still utilizing [[Romano-British]] ideals and conventions. Historian [[Stuart Laycock]] has investigated this process and emphasised elements of continuity from the British tribes in the pre-Roman and Roman periods, through to the native post-Roman kingdoms.<ref>{{Harvp|Laycock|2008}}.</ref>

In British tradition, pagan Saxons were invited by [[Vortigern]] to assist in fighting the [[Picts]], [[Scoti]], and [[Déisi]]. (Germanic migration into Roman Britannia may have begun much earlier. There is recorded evidence, for example, of Germanic [[auxilia]]ries supporting the legions in Britain in the 1st and 2nd centuries.) The new arrivals rebelled, plunging the country into a series of wars that eventually led to the Saxon occupation of Lowland Britain by 600. Around this time, many Britons fled to [[Brittany]] (hence its name), [[Britonia|Galicia]] and probably [[Ireland]]. A significant date in sub-Roman Britain is the [[Groans of the Britons]], an unanswered appeal to [[Flavius Aetius|Aetius]], leading general of the western Empire, for assistance against Saxon invasion in 446. Another is the [[Battle of Deorham]] in 577, after which the significant cities of [[Bath, Somerset|Bath]], [[Cirencester]] and [[Gloucester]] fell and the Saxons reached the western sea.

Historians generally reject the [[historicity of King Arthur]], who is supposed to have resisted the Anglo-Saxon conquest according to later medieval legends.<ref>{{Cite book |last=Higham |first=Nicholas J. |title=King Arthur: The Making of the Legend |publisher=Yale University Press |year=2018 |isbn=978-0-3002-1092-7 |location=New Haven, Connecticut}}</ref>