Editing Roman Britain (section)

=== 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>