Collapse of society ?

[Flavivs Aetivs]

a rise in organised banditry (the bagaudae)

The 5th century Bagaudae moreso consisted of local possessores looking to their own administration and defense to eliminate the tax burden from the Roman government with a much lighter one. Eventually they became the Armoreciani, and it seems that in 447-452 the Spanish Bacaudae even nominated their own emperor, if the name of their leader Basiliscus means anything.

AFAIK, I thought the lack of Roman government in Britain created an economic boom in the 5th century?