Great Conspiracy

The Great Conspiracy
Part of the Roman occupation of Britain
Northern Roman Britain, c. 350–400 AD.
Date 367–368 Location Roman Britain Result Roman victory
Belligerents
Roman Empire	Picts Scoti Attacotti Saxons Franks Roman deserters rebellious Britons
Commanders and leaders
Nectaridus † Fullofaudes Severus Jovinus Count Theodosius	Valentinus and others

The Great Conspiracy was a year-long state of war and disorder that occurred near the end of Roman rule in Britain. Fourth-century Roman historian Ammianus Marcellinus describes it as a barbarica conspiratio ('barbarian conspiracy') which took advantage of a depleted military force in the province; many soldiers had marched with Magnentius in his unsuccessful bid to become emperor. Few returned, and supply, pay, and discipline in the following years may have been deficient.

The precise chronology of events remains unclear. Ammianus, although being the author of the most comprehensive and widely-cited surviving sources on the Conspiracy, was living in Antioch during the time that it took place. His account is thus likely to be derived from other sources and exhibits inconsistencies with other known documentation.^[1]