When Governor Gaius Suetonius Paulinus prepared to face Boudica’s enormous rebel army, he needed every soldier could gather. Legio XIIII Gemina answered his call, along with part of Legio XX Valeria Victrix and the auxiliary troops available to him. One legion, however, never arrived. Legio II Augusta remained in western Britain while Suetonius fought the decisive battle of the revolt. Its absence has produced an enduring historical mystery: Why did one of Rome’s most experienced legions fail to march when the province was facing destruction? The frustrating answer is that our surviving evidence tells us what happened, but not why.
What Tacitus Tells Us
Our principal source is the Roman historian Tacitus, writing approximately fifty years after the revolt. In Book 14 of his Annals, Tacitus says that the commander responsible for Legio II Augusta was Poenius Postumus, the legion’s praefectus castrorum, or camp prefect. According to Tacitus, Postumus refused the governor’s order to bring his legion to the battle. Suetonius therefore faced Boudica with a force of only around 10,000 men. Despite being heavily outnumbered, the Romans won a crushing victory. Tacitus then describes what happened when the news of the victory reached Postumus. After learning of the success won by Legio XIIII and the detachments of Legio XX, Postumus realized that he had deprived his own legion of an equal share in the glory. Having disobeyed the governor’s command, he fell upon his sword. That is everything our surviving literary evidence tells us about his decision. Tacitus gives Postumus no speech, explanation or defense. Cassius Dio, whose account of the revolt was written considerably later, does not mention the incident.
A Decision Made by One Officer
It is important to distinguish between the actions of Postumus and those of his soldiers. There is no evidence that the legionaries of Legio II Augusta mutinied, refused to fight or voted to remain behind. The decision appears to have belonged to their acting commander. The camp prefect was normally the third ranking officer in a legion, below the senatorial legate and the senior military tribune. He was usually an experienced soldier who had risen through the ranks and often completed a long career as a centurion before receiving the appointment. Postumus was therefore unlikely to have been an inexperienced or timid officer. Why he was commanding the legion during the revolt is uncertain. Its legate and senior tribune may have been absent with Suetonius, detached elsewhere or otherwise unavailable. Whatever the circumstances, Postumus found himself responsible for making a decision that would determine the fate of thousands of men.
Where Was Legio II Augusta?
Archaeological evidence places a legionary fortress at Isca Dumnoniorum, modern Exeter, beginning around AD 55. The fortress is generally associated with Legio II Augusta, which had participated in the conquest of southwestern Britain. If a substantial part of the legion was stationed at Exeter when the revolt began, it was a considerable distance from the main area of fighting. Suetonius was moving through southeastern and central Britain while Boudica’s forces destroyed Camulodunum, Londinium and Verulamium. The precise location of Suetonius’s final battle remains unknown, which makes it impossible to reconstruct the route Legio II would have taken to reach him. It would probably have required a long march through unsettled territory while the location and intentions of the rebel army were uncertain. Roman roads allowed armies to move quickly, but communications still depended on mounted messengers. By the time Postumus received his orders, the military situation may have changed. This is a reasonable possibility, but it remains a reconstruction rather than a recorded fact.
Did Postumus Believe the Battle Was Already Lost?
Postumus may have believed that Suetonius was leading the remaining Roman army into disaster. The evidence available to him could hardly have been encouraging. Camulodunum had fallen. Londinium and Verulamium were destroyed. A force from Legio VIIII Hispana had attempted to stop the rebellion, only to have its infantry overwhelmed and wiped out. Suetonius had even abandoned Londinium after deciding that he lacked the soldiers and defenses necessary to protect it. Against that background, marching Legio II Augusta across the province may have appeared dangerously reckless. Postumus might have feared that his legion would be intercepted and destroyed before it ever reached the governor. He may also have believed that removing the legion from the southwest would leave recently conquered territory, military installations and Roman supply lines dangerously exposed. It is also possible that the entire legion was not concentrated in one place. Roman Legions frequently sent detachments to occupy forts, protect roads, escort supplies and preform construction work. Postumus may not have had a complete legion immediately ready to march. All of these explanations are possible; however none can be proven.
Cowardice, Caution or Disobedience?
Tacitus present the incident in moral and military terms. Postumus had disobeyed the orders of his governor and denied his soldiers their chance to share in a celebrated Roman victory. Within the Roman army, that was a serious failure regardless of the reason behind it. Calling Postumus a coward, however, goes beyond the evidence. As an experience former centurion and camp prefect, he had probably spent much of his life in military service. His decision may have been driven by fear, but it may equally have resulted from caution, incomplete information or an honest belief that Suetonius’s position was hopeless. His suicide does not answer the question. Once Suetonius had won, Postumus faced the consequences of disobeying a direct order during the greatest military crisis Roman Britain had yet experienced. He had damaged his reputation, dishonored his command and possibly exposed himself to trial and execution. Taking his own life allowed him to accept personal responsibility in a way that Roman military culture could understand.
A Mystery the Evidence Cannot Solve
The safest conclusion is that Legio II Augusta did not collectively refuse to fight Boudica. Its acting commander refused or failed to obey an order to bring the legion to Suetonius. Tacitus condemns the decision but never explains what motivated it. Postumus may have misjudged the situation. He may have believed Suetonius was doomed, feared losing the legion during the march or considered the southwest too important to abandon. Whatever his reasoning, Suetonius won without him, while Legio XIIII Gemina and the participating soldiers of Legio XX gained the glory of saving the province. Legio II Augusta’s absence is therefore not a story with a clear answer. It is a reminder of the limits of our evidence. We know the order was given, we know Postumus did not obey it, and we know how he reacted when the battle was won. Everything between those points will more than likely always remain uncertain.
Legio XIIII, Protinus!
