Poenius Postumus

Poenius Postumus was praefectus castrorum of the Roman Legion II Augusta, stationed in Britain during the rebellion of Boudica in 61 AD. In the general area of Exeter with his troops, he ignored the call to join the governor, Gaius Suetonius Paulinus, in putting down the rebellion. Hearing of the Roman victory at the Battle of Watling Street, having denied his troops a share in the glory, he fell on his sword.

It's very unlikely, as said at the time, that Postumus refused to obey the orders he received due to cowardice. As Praefectus Castrorum he would have served as Primus Pilus of II Augusta or another prime legion. Thus, he was an experienced and brave veteran soldier, trained, above all, to obey orders. Most likely, either he didn't believe that the orders were genuine, and suspected a trap, or he had received other misleading intelligence that the two legions with the Governor had already been defeated, leaving him in command of the only remaining effective military force in the Province.

The II Augusta are known to have been based at Exeter in Devon. The praefectus castrorum or camp prefect was normally promoted from the ranks, and was third-in-command of a legion's command structure. In this case, the decision whether to move the troops to help put down the rebellion fell to Postumus, implying that the legate and the senior tribune were unavailable, probably acting as members of Suetonius Paulinus's staff during the campaign on the island of Anglesey, which preceded the revolt.

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