After The Boom, There is The Bust
The boom period in Roman Britain had ended by the middle of the third century as an increasing amount of resources were plowed into defense. A Gallic Empire was formed during the Crisis of the Third Century in 259 AD, and Britain was part of it. Emperor Aurelian was able to sew the Empire back together in 274 AD, but there was little that could be done to prevent its downfall.
The Carausian Revolt (led by Roman General Carausius) in 286 AD led to the creation of the Britannic Empire which was independent of Rome. He was murdered by Allectus seven years later, and the usurper ruled Britain until 296 AD. In that year, the Romans took back Britain and Allectus died in battle.
There was a brief revival in the early part of the fourth century during the reign of Constantine the Great. He encouraged the improvement of fortifications and roads in Britannia but in 350 AD, another usurper, Flavius Magnus Magnentius, took control as he seized the imperial crown in the West. At this point, the frontiers of Roman Britain were under almost constant attack from Pictish and Scottish tribes. There were attacks in 367-68, 382, and 396-98.
The beginning of the end came with the death of Emperor Theodosius in 395 AD; his empire was divided among his two sons; Honorius took the East, and Arcadius had the West. While the Eastern Empire was thriving, the West was on the brink of collapse. By the beginning of the fifth century, Italy was under attack and Stilicho, the most powerful military presence in Rome withdrew the vast majority of legions in Britain. At the same time, Germanic raiders were attacking the Southern and Eastern coasts of England.
In 405 or 406 AD, the Vandals, Alans, and Suebi crossed the Rhine and caused chaos in Britain. Constantine III took charge of the troops in Britain in 407 AD and tried to establish himself as Roman Emperor in the West. The natives apparently expelled the Roman administration in 409 AD, and when they asked Emperor Honorius to help with the invaders in 410 AD, he told them to fend for themselves. This response marked the end of Roman influence in Britain.
By 425-430 AD, Britain was in no way, shape or form ‘Roman’ as villas had been abandoned, mosaic and fresco workshops had closed, and barter replaced money. London was in ruins by 430 AD, and Roman culture and organization had disappeared by 600 AD. Attempts to salvage the Empire in the West were in vain as the last emperor was deposed in 476 AD. Although many Roman cities in Britain fell into decay, others were expanded later on, and places such as Canterbury remain occupied to this day.
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