This Week in History - Caesar crosses the Rubicon (10 January)

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A Roman aristocrat, Gaius Julius Caesar was a very successful general, in Spain in the late 60s BC, and in Gaul in the 50s. Caesar was a fast, decisive, determined and adaptable general, enabling him to subdue the famously bellicose Gauls. Like most Romans, he used this experience to propel himself up the political ladder, but much more distinctively, Caesar also used the power and prestige gained through military success to become the sole dictator of the Roman Republic.

Caesar's victories in Gaul had amassed him great power, and a large, effective, and loyal army. By the last years of the 50s, the powerful men back in Rome, the Optimates, fearing Caesar's power and abilities, started to act against him, trying to limit his scope for action, hoping that by stopping him achieving his next aim, a consulship in 48, they might be able to bring him down. Caesar resented this, but to his credit, negotiated with Pompey until early January 49, when finally the Senate formally declared against Caesar, decreeing that he must dismiss his army by an appointed day and granting Pompey and the other magistrates increased authority to deal with the situation. Caesar felt this left him little choice but to fight, and on 10 January 49, Caesar made the momentous decision to cross the Rubicon at the head of an army, an action which instantly made him an enemy of Rome. The civil war that followed was an all out victory for Caesar. He defeated Pompey, Antony, and their supporters, and became the dictator of Rome. It is hard to tell whether he wanted to become dictator, or whether it was the only way he thought he could secure and maintain the supreme position at Rome which he felt he deserved. It is also difficult to know whether he realised that his actions would destroy the Republic for which he had fought so many wars. Whatever his motives, it is clear that others did not agree with his position.

On the Ides of March 44 (the 15th), Caesar was stabbed to death by a group of conspirators, some of which were his own supporters. The conspirators may have thought they were restoring the Republic, but their subsequent inaction allowed Octavian, later the Emperor Augustus, to return to Rome, claim Caesar's heritage, and win the following bloody civil war, which put the last nail in the coffin of the Roman Republic.

Further Reading
Essential Histories 43: Caesar's Gallic Wars 58-50 BC is a detailed narrative of Caesar's time in Gaul, the context and background of the war, and includes some fascinating comparisons of Roman and Gallic armies, and Essential Histories 42: Caesar's Civil War 49-44 BC follows Caesar after his return from Gaul, charting his battles with Pompey and his followers, his short dictatorship and death (extract below). For more information about Caesar's enemies the Gauls, Men-at-Arms 158: Rome's Enemies (2) Gallic and British Celts has detailed text and brilliant illustrations by Angus McBride, showing the warring Celts throughout their history. For a similar discussion of another of Caesar's foes, the Germans, look at Men-at-Arms 129: Rome's Enemies (1) Germanics and Dacians For information on the Roman Army and their clothing in this period, the authoritative Men-at-Arms 374: Roman Military Clothing (1) 100 BC-AD 200 by Graham Sumner is fascinating and rich with detail covering every aspect of the clothing worn by Roman soldiers, right down to their socks... Men-at-Arms 46: The Roman Army from Caesar to Trajan illustrates the Roman army in the period after Caesar's death and into the Empire and Warrior 71: Roman Legionary 58 BC-AD 69 details the daily lives of the men who fought for Caesar and his successors. New Vanguard 78: Greek and Roman Siege Machinery 399 BC-AD 363 is an insight into another aspect of ancient war, the evolution of the arsenal of weapons at Caesar's disposal in Gaul and beyond.


An extract from Essential Histories 42: Caesar's Civil War 49-44 BC

The civil war 

By the end of the Gallic campaigns, Caesar commanded ten legions (numbered V to XIV). Two more, XV and I, the latter on loan from Pompey's Spanish armies, had been withdrawn earlier in 50 to be sent against the Parthians. The majority of these troops were seasoned veterans, utterly devoted to Caesar and confident in their own and their commander's ability. In support were bands of excellent Gallic and German cavalry. To match against this Pompey had seven legions garrisoning his Spanish provinces, although these had little actual combat experience. There were also the I and the XV which had not yet left for the east and were still in Italy, but as both had recently served under Caesar their loyalty appeared questionable. However, he boasted that he had only to stamp his foot in Italy for more legions to appear, and was also sure of the loyalty of the eastern provinces which he had reorganised just over a decade before. In the long term, Pompey could probably claim greater resources than Caesar, but it would take time to mobilise these into field armies.

In 49 Pompey was almost 58, but remained an extremely fit and active man, and others marvelled at the energy he showed in joining the training exercises of his soldiers. His military record was extremely good, even if he had made something of a habit of arriving in the last stages of a conflict to claim the credit largely won by someone else. He was certainly a brilliant organiser, as the campaign against the pirates, as well as, more recently, his supervision of Rome's corn supply, had shown. In his youth he had been a bold commander, on several occasions leading charges in person, but his aggression, in a properly Roman way, had always been based on sound preparation. However, although he was only six years older than Caesar, Pompey had spent the last decade in Rome and had not served on campaign since 62. His performance during the Civil War would suggest that he was past his best as a general. He was not helped by the presence of so many distinguished senators in his camp. Unlike Caesar, whose followers were undistinguished and whose authority was unchallenged, Pompey was always under pressure to alter his plans. Most of the senators who flocked to his cause had more prestige than ability, and on more than a few occasions proved a positive hindrance. The ablest of his subordinates, Titus Atius Labienus, had served with Caesar throughout the Gallic campaigns. It is probable that he had a prior connection with Pompey, for he defected from Caesar's camp at the beginning of the war. On hearing of this, the latter ordered his baggage to be sent on after him.

Caesar failed to attract any distinguished supporters from the senior members of the Senate. Now in his early 50s, he was still very much at the peak of his ability, and was fresh from a decade of successful fighting in Gaul. His strategy during the Civil War, as in Gaul, was based on rapid offensives, sometimes in the face of great odds. Though often criticised for recklessness by modern commentators, it is important to emphasise that such boldness was characteristically Roman, and should not conceal that much preparation underlay these enterprises. Although subject to occasional epileptic fits, he was in other respects an extremely healthy and active man, capable of massive effort and rapid long-distance travel. Caesar promoted and lavishly rewarded any soldiers who distinguished themselves, but even more than this it was his remarkable charisma that ensured that his soldiers were devoted to him. Throughout the war, desertions from the Pompeian forces were common, but all of our sources claim that there were no defections in the other direction. Fighting a war to protect his own honour and status, Caesar's objective was clear and obvious, giving the Caesarian war effort a unity of purpose not displayed by the other side. Yet it also meant that it was much easier for him to lose. If Caesar were killed, or his army defeated so heavily that he was discredited, then the war would effectively have been over. Only the Pompeians could suffer defeat after defeat and still prolong the struggle.

It is hard now to say whether Pompey or Caesar was the better general. The vast bulk of our evidence comes, directly or indirectly, from Caesar's version of events. His Commentaries obviously present his own actions in a favourable light, while dismissing those of the enemy. However, they also provide evidence that allows the wisdom of some of Caesar's decisions to be questioned. Yet, for the Romans the answer was obvious, for the most important attribute of a great general was that he won his wars. Caesar defeated Pompey, and in the end there was no more to be said.

An extract from Warrior 71: Roman Legionary 58 BC-AD 69
Leadership and Morale
 

The Roman legion is often described as a military machine, but the legion was only as good as the sum of its men and this was dependent on their morale. Legionaries were as apt to panic and as susceptible to defeat as any other demoralised soldiers throughout history. For example, when the army of Aulus Caecina was retreating through Germany in AD 15, it found itself in a situation similar to that which had destroyed the army of Varus. The Roman soldiers despaired:

There were no tents for the centuries, no dressings for the wounded, and as they divided their rations, foul with dirt or blood, they bewailed the deathlike gloom and that for so many thousands of men but a single day remained. A stray horse that had taken fright at their shouting and broken free of its tether, threw into confusion the men who ran to stop it. So great was the consequent panic - men believed the Germans had broken in - that there was a general rush to the gates ... principally the gate facing away from the enemy. (Tacitus, Annals, 1.65-66)

Commanders had to act quickly to stem the onset of panic and despair. The forbearance of Caecina held his army together:

Caecina, satisfied that their fear was groundless, still found command, entreaty and even force to no avail, threw himself flat in the gateway; and only shame barred a road that led over the general's body. At the same time the tribunes and centurions explained that it was a false alarm. He now paraded the soldiers in front of his headquarters, ordering them to listen in silence, warning them of the crisis and its urgency. 'Salvation lies in our arms, but we must be careful and remain within the rampart till the enemy approaches, hoping to storm the camp. Then we will erupt from all sides and make for the Rhine! If we flee, we can expect more forests, deeper swamps and a brutal enemy. But if victorious, glory and honour!' He reminded them of all they loved at home, all the honour they had gained in camp, but said nothing of their adversity. Then, with complete impartiality and beginning with his own, he distributed the horses of the legates and tribunes to men of great bravery. These were to charge first, followed by the infantry. (Tacitus, Annals, 1.66-67)

Caecina's plan succeeded. As the unsuspecting Germans debated how to assault the camp, the Romans charged down the ramparts, routing and pursuing their enemy until nightfall (Tacitus, Annals, 1.63-68).

Legionaries thrived on the charismatic and fair leadership of their officers. Caesar, Antony, Germanicus, Caecina and Vespasian are obvious examples of generals willing to lead by example and share the soldiers' hardships. The centurions frequently cited by Caesar and Josephus were courageous and steady, able to assert their authority in crisis situations and avert the onset of panic among the rank and file. But not all officers had the necessary confidence, courage or charisma to lead their men effectively. Many were brutal and corrupt. When fair leadership was lacking, performance in battle was poor and legionaries were readily disposed towards mutiny and rebellion.

Velleius Paterculus, who served as a legionary legate during the Illyrian Revolt of AD 6-9, emphasises that the disintegration and destruction of Quinctilius Varus' army in the Teutoburg Forest (AD 9) was caused by the poor leadership and cowardice of Varus and his senior officers:

An army unexcelled in bravery, the first of the Roman armies in discipline, energy and experience in the field, through negligence of its general, the treachery of the enemy and the unkindness of Fortune was surrounded, nor was as much opportunity as they had wished given to the soldiers either of fighting or of extricating themselves, except against heavy odds; indeed, some were even chastised for using their weapons and showing the spirit of the Romans. Hemmed in by forest, marshes and ambuscades, it was destroyed almost to a man by the very enemy it had always slaughtered like cattle. ... the general had more courage to die than to fight ... [and] ran himself through with his sword. The two camp prefects ... after most of the army had been destroyed, proposed its surrender, preferring to die by torture ... than in battle. [The legate] Vala Numonius ... previously an honourable man, set a fearful example by leaving the infantry unprotected by the cavalry, attempting to flee to the Rhine. Fortune avenged his act ... he died in the act of desertion. Varus' body, partially burned, was mutilated by the enemy; his head cut off. (Velleius Paterculus, 2.119)

The mutiny of the Pannonian legions at Emona in AD 14 was caused in part by the corruption and brutality of centurions and senior officers. The mutineer Percennius complained that from his pay he had to 'buy clothes, weapons and tents, [and] bribe the bullying centurion to purchase a respite from duty.' His comrades killed the centurion Lucilius, who was known as 'Fetch Another' because of his habit of breaking vine sticks while flogging legionaries and calling for a replacement (Tacitus, Annals, 1.17, 23). The excessive discipline of the camp prefect, Aufidienus Rufus, was repaid in kind. He was seized by a detachment of legionaries repairing roads and bridges:

Dragged from his carriage, loaded with baggage and driven at the head of the column, he was plied with sarcastic enquiries whether he found it pleasant to support these huge burdens and these endless marches. For Rufus, long an ordinary soldier, then centurion and ultimately camp prefect, sought to reintroduce the old hard discipline; he was habituated to work and toil and pitiless because he had endured. (Tacitus, Annals, 1.20)

The corruption of centurions also undermined the morale of Otho's German legions in AD 69:

The soldiers demanded that the payments usually made to centurions to secure leave should be abolished, since they amounted to an annual tax on ordinary soldiers. A quarter of each century would be away on leave or loafing about the camp itself, provided the soldiers paid the centurion his price, and no-one cared how the burden pressed on the soldiers or how they got their money. In reality it was through highway robbery, petty thieving and by menial jobs that the soldiers purchased rest from military service. The richest soldiers would be assigned the worst fatigues until they purchased relief. Then impoverished and demoralised by idleness, the soldier returned to his century poor instead of wealthy and lazy instead of energetic. So ruined one after the other by the same poverty and lack of discipline, they were ready to rush into mutiny and dissension and ultimately into civil war. But Otho wished to avoid alienating the centurions, so he promised that the imperial treasury would pay for annual leave, a procedure which was undoubtedly useful and later established by good emperors as a fixed rule of service. (Tacitus, Histories, 1.46)

Even when corruption and brutality were (apparently) lacking, legionaries were unwilling to follow particular officers into battle. There is a strong impression that the flight of a cohort of legio III Augusta from an engagement against Tacfarinas in AD 18, was influenced not only by the number of the enemy, but by the unwillingness of the legionaries to follow a glory-seeking officer:

[Tacfarinas] invested a Roman cohort not far from the River Pagyda (Tunisia). The fort was commanded by Decrius, who, energetic, vigorous and experienced in war, considered the siege a disgrace. After addressing the men, he drew up his lines in front of the fort and offered battle. As the cohort broke on the first onset, he darted eagerly among the missiles to intercept the fugitives, cursing the standard-bearers who could see Roman soldiers turn their backs to a horde of untrained men and deserters. At the same time, he turned ... with one eye pierced, to confront the enemy and fought until he dropped, deserted by his men. (Tacitus, Annals, 3.20)

Legionaries did not want to follow men who could get them killed unnecessarily.