4th century in Roman Britain

Events from the 4th century in Roman Britain.

Events

 * 301
 * Emperor Diocletian fixes the prices of British woollen goods and beer.
 * 306
 * 25 July – Emperor Constantius Chlorus dies at Eboracum (York), after campaigning against the Picts. His son Constantine the Great is acclaimed as his successor by the troops here.
 * 314
 * The reforms of Diocletian take effect, dividing Britain into four provinces and separating military and civilian government.
 * Establishment of initial Christian hierarchy in Britain.
 * Three British bishops attend the Council of Arles.
 * 343
 * January – Emperor Constans visits Britain, and strengthens northern frontier and Saxon Shore.
 * Construction of Pevensey Fort.
 * 353
 * Roman Emperor Constantius II punishes British supporters of the recently defeated usurper, Magnentius, and suppresses paganism.
 * 355
 * Julian the Apostate placed in charge of Britain and Gaul.
 * 359
 * Julian makes Britain main granary for western Roman army.
 * 360
 * Picts and Irish attack northern frontier.
 * 367
 * The Great Conspiracy: Sustained raids by Picts, Irish, and Saxons. Hadrian's Wall abandoned and military commander Fullofaudes captured or killed.
 * 368
 * Count Theodosius arrives in Britain with a military task-force, restores administration under Governor Civilis and commander Dulcitius.
 * 369
 * Theodosius defeats invaders, builds new watchtowers from Filey to Huntcliff, re-fortifies northern frontier.
 * 382
 * Magnus Maximus defeats the Picts and Scots.
 * 383
 * Maximus usurps control of the Empire, taking troops from Britain and abandoning the forts at Chester and the Pennines.
 * 397
 * Saint Ninian converts the region around Galloway to Christianity.