The 'Barbarian Conspiracy'of 367 A.D.

Background.

In 360 A.D. , Caesar Julian was over-wintering in Paris during his campaign against the Alemanni in north east Gaul. He was informed that strong Pictish and Irish raids were being launched against Britannia. Julian sent a Batavian and a Heruli unit and two units of Moesiaci under magister militum Lupicinus to deal with this problem.

Emperor Constantius was jealous of Julian's military successes and popularity with the army. He sent orders for Julian to send his best two units plus 300 men from each of his other units for duty with the Emperor. The Batavi & Heruli units sent to Britian are specifically mentioned. It would appear that Julian had sent them & his pro-Constantius commander, Lupicinus, to Britain and out of contact with Constantius. Julian was proclaimed Emperor by his remaning troops. He marched East to fight his cousin, but before Julian reached Constantinople, Constantius had died. Julian ruled as Emperor for three years before being killed by one of his own men whilst fighting the Persians.

Four years

The 'barbarica conspiratio' (the Barabian Conspiracy).

In 367 A.D., a large Barbarian raid swamped the garrision of Britannia. The Areani or Arcani (the word depends on the reading of the original manuscript), who were a military unit of spies or scouts, assisted the Barbarians. It sems that they either took bribes to not inform the Roman forces of the forthcoming attack and/or supplied information on Roman troop dispositions to the enemy.

The forces of Hadrian's wall were defeated or by-passed, Nectaridus, the comes maritimi tractus (Count of the Maritime Region) was killed and Fullofaudes, the dux Britanniarum (Duke of Britain) was beseiged or captured. Several units of the army appear to have disintgrated or deserted their posts.

Emperor Valentinian was (also) on campaign against the Alemanni and ordered firstly Severus, his comes domesticorum and then Jovinus, the magister equitum to restore order. Both failed.

In spring 368, four units, the Batavi, the Heruli, the Iovii and the Victores formed a force commanded by Comes Rei Militaris Theodosius (father of the future Emperor Theodosius the Great) which was sent by Valentinian to deal with the situation. Landing at Richborough, they marched to London to re-establish central authority.

A rebellion, lead by Valentinus, a Pannonian army officer who had been banished to Britainnia, broke out. He offered the deserters of the Britannian garrison large rewards to join him. Theodosius quickly captured and executed him. Theodosius also offered an amnesty to all deserters if they rejoined their units. He then spent the next year rebuilding the Britannian garrision and dealing with the remaining Barbarian raiders.

Sources:

Ammianus Marcellinus. The Later Roman Empire (A.D 354-378). Penguin Classics, Harmondsworth, 1987.

Esmonde Cleary, A.S. The Ending of Roman Britain. Batsford, London, 1989.

Frere, Sheppard. Britannia. Book Club Associates, London, 1987.

Johnson, Stephen. Later Roman Britain. Paladin, London, 1986.

Salway, Peter. Roman Britain. Oxford University Press, 1981.