Julius Caesar: towards the Rubicon (59-49 BC)

The presumed course of the Rubicon, the boundary between Rome and Cisalpine Gaul.
It was never a major river. Now it is only a stream

Caesar in Gaul

In 59 a friendly tribune had secured Caesar the command of the provinces of Illyricum (the Dalmatian coast) and Cisalpine Gaul (northern Italy) for five years, with three legions and the right to found colonies.  Cisalpine Gaul was near enough to Rome to allow him to keep in touch with events. However the death of the allotted commander for Transalpine Gaul (Gallia Narbonensis), at a time when it was threatened by hostile tribesmen, caused the senators to panic and add it to his provinces. But it seems that this command was only granted on a yearly basis and was less secure than the other two.

Gaul and the Roman world on the eve
of the Gallic War

Caesar’s campaigns against the Gauls were described in his Gallic War. Between 58 and 56 the Romans over-ran the greater part of Gaul, though the Veneti of Brittany were still causing trouble and were only defeated after a naval battle, after which the elders of the tribe were massacred and the rest sold into slavery. 

In the spring of 56 Caesar took time off from his campaigns to return to cement the agreement with Pompey and Crassus at Lucca in Cisalpine Gaul: Pompey and Crassus were to be elected consuls in 55 and each of them would then be given five-year commands in the provinces. This unconstitutional arrangement meant that Caesar’s command in Gaul could also be extended. The three members of the triumvirate now had direct control of twenty legions and Rome’s most critical provinces. As Tom Holland says, 

‘The city had often echoed to cries of ‘tyranny’ – but never, surely with such justification as now.’  

In 55 BC Caesar crossed the Rhine over a specially constructed bridge and drove the Germanic tribes east. In July 55 he launched his attack on Britain, on the excuse that the British tribes had given help to the Veneti.  He probably landed at Walmer. The tribal chieftains of Kent submitted, but a storm wrecked his ships and he was forced back to Boulogne. The expedition was a failure but nothing like this had been attempted before and the news caused a sensation in Rome.

In 54 he returned to Britain with five legions and 2000 Gallic cavalry. He met and defeated the Kentish forces near Canterbury, crossed the Thames and defeated Cassivellaunus, the king of the Catuvellauni in Hertfordshire.  Though Caesar spun this as a victory, he had over-reached himself and was forced to return to Gaul to put down a revolt there. However, he left a legacy of ambition for his successors. 

The breakdown of the Triumvirate

Meanwhile in Rome Pompey and Crassus were elected joint consuls for the second time in 55 BC. Crassus went off to defeat the Parthians in north-east Iran, but though he had been given two Spanish provinces Pompey chose not to campaign in person but to remain in Rome, where he dedicated his very lavish new theatre in the Campus Martius, which may interpreted as a sign of his overweening arrogance. In 54 Pompey’s wife Julia (Caesar's daughter) died in childbirth. This severed much of the bond between Caesar and Pompey. In 53, the shocking news came that Crassus had been defeated and killed by the Parthians. It was Rome's greatest humiliation since the time of Hannibal.

Rome in anarchy

In 52 Rome began once more to disintegrate into anarchy and gang warfare. The former tribune P. Clodius was killed and a fire destroyed the Senate-house.  The Senate in panic granted Pompey emergency powers and made him sole consul; even the republican, Cato, felt that this was necessary. Pompey rose to the challenge, passed some tough laws to contain the violence and restored political normality by having a colleague (the father of his new wife, Cornelia) appointed consul in the same year. He had thus resisted the temptation to turn himself into a dictator on the model of Sulla.

Gaul: the final victory

In the same year Caesar faced another Gallic threat, this time from the great leader, Vercingetorix.  He put this down in September 52 at Alesia (near modern Dijon) in an extraordinary victory. He then moved south and took up his winter quarters in Ravenna in Cisalpine Gaul. 

Caesar marches south

News of Caesar’s victory reached Rome in the middle of 52. For the Senate it was a cause of alarm as much as celebration. They had become uneasy about his long tenure of command and they wished to prosecute him for illegally extending its term. Caesar for his part sought the same treatment that had been given to Pompey: the right to remain in command of his province and to hold the consulship again.  But this was intolerable to many in the Senate; if he were permitted to progress from a military command to a second consulship, he would at no stage be a private citizen and thus he would be immune from prosecution.  Moreover, in his campaigns he had amassed an astounding fortune. When he returned to Rome he would easily have enough money to bribe the citizens and he had battle-hardened veterans under his command to intimidate his opponents.

The Senate then moved against Caesar, who was now stationed at Ravenna in Cisalpine Gaul with the Thirteenth Legion.  On 7 January 49 BC a state of emergency was proclaimed and Pompey moved his troops into Rome.  The Senate then passed the senatus consultum ultimum, which would have outlawed Caesar if he returned to the Republic. Caesar’s ally in the Senate, the tribune Marcus Antonius, and two other allies of Caesar, disguised themselves as slaves and fled to Ravenna. 

On (probably) 10 January Caesar advanced with his troops from Ravenna to Ariminium. In doing so, he crossed the Rubicon, the narrow stream that separated Cisalpine Gaul from Italy and broke Rome’s law of treason that forbade a governor to exercise imperium (the right to command) outside his allocated province. (This law had been formulated by Sulla with the aim of curbing such acts against the government.) In crossing the river, Caesar is alleged to have said, 

‘The die is cast’. 

The Civil War had begun.