Caesar's civil war

Caesar's Civil War
Date	49–45 BC
Location	Italy, Hispania, Greece, Egypt, North Africa and Asia Minor
Belligerents	Caesarian faction Pompeian faction and senatorial allies
Commanders	Gaius Julius Caesar Mark Antony Marcus Aemilius Lepidus Gaius Scribonius Curio
Opposing Leaders	Pompey the Great Cato the Younger Metellus Scipio Titus Labienus Gnaeus Pompeius
Major Engagements	Battle of Ilerda Battle of Dyrrhachium Battle of Pharsalus Battle of the Nile Battle of Thapsus Battle of Munda
Result	Caesarian victory; defeat of the principal Pompeian armies; Caesar's establishment as the dominant ruler of Rome

Caesar's Civil War (49–45 BC) was a major conflict of the late Roman Republic between the forces of Gaius Julius Caesar and those supporting Pompey the Great and the senatorial opposition. The war began when Caesar led his army across the Rubicon River in January 49 BC, entering Italy in defiance of the Roman Senate's demand that he relinquish his provincial command. The conflict subsequently extended across Italy, Hispania, Greece, Egypt, North Africa and Asia Minor. It ended with Caesar's victory over the remaining major Pompeian army at the Battle of Munda in 45 BC.

The war was one of the decisive events in Roman history. It destroyed the remaining political balance between Rome's competing aristocratic factions and established Caesar's personal supremacy over the Roman state. Although republican magistracies and institutions continued to exist, the Republic could no longer operate independently of Caesar's authority. His assassination in 44 BC did not restore the former political order; instead, it initiated another period of civil war which ultimately resulted in the establishment of the Roman Empire under Augustus.

Background

The political relationship between Caesar and Pompey had originally been one of cooperation. Together with Marcus Licinius Crassus, they had formed the political alliance known as the First Triumvirate. Caesar's daughter Julia had married Pompey, strengthening their personal relationship. Caesar's subsequent conquests in Gaul, however, greatly increased his military reputation, wealth and political influence.

The death of Julia in 54 BC and the death of Crassus during the Roman campaign against Parthia in 53 BC weakened the political arrangements which had previously united the three men. Pompey increasingly associated himself with Caesar's opponents in the Senate and eventually became the principal military leader of the senatorial faction.

The immediate dispute concerned Caesar's provincial command and his return to Rome. Caesar wished to retain his command until he could stand for another consulship without surrendering the legal protections and military authority associated with his position. His opponents demanded that he relinquish his army and return to Rome as a private citizen, where he could face legal and political challenges. Pompey and his senatorial supporters regarded Caesar's continued command as a threat to the authority of the Republic, while Caesar regarded the demands as an attempt to destroy his political position.

The dispute was not simply a personal disagreement between two generals. It involved constitutional questions concerning the authority of the Senate, the rights of elected magistrates and tribunes, the duration of provincial commands and the influence of military power in Roman politics. Modern historians continue to debate the responsibility of the competing political factions for the breakdown of negotiations and the outbreak of war.

Outbreak of war (49 BC)

In January 49 BC the Senate adopted the emergency decree known as the senatus consultum ultimum, authorising measures to protect the Republic. Caesar's supporters among the tribunes, including Mark Antony and Quintus Cassius, left Rome after their political position became untenable. Caesar subsequently claimed that the rights of the tribunes had been violated and used their treatment as a justification for his intervention.

In early January Caesar crossed the Rubicon River with troops of the Thirteenth Legion. The river marked the boundary between his provincial command in Cisalpine Gaul and Italy proper. A Roman governor was not entitled to bring a provincial army into Italy without authorisation. Caesar's crossing therefore amounted to an armed challenge to the existing political authority of the Senate.

The expression "crossing the Rubicon" subsequently became a familiar description of an irreversible decision. Ancient accounts associate the event with Caesar's famous declaration that the die had been cast, although the precise words attributed to him differ between the surviving sources.

Caesar advanced rapidly through Italy. Pompey and a substantial part of the Senate withdrew from Rome and eventually crossed the Adriatic Sea to Greece, where Pompey intended to organise a larger army. Caesar's advance was marked by the surrender of several towns and the capture of the important position at Corfinium. There he accepted the surrender of Pompeian forces and released a number of prominent captives, including Lucius Domitius Ahenobarbus. Caesar presented such acts of clemency as evidence that he intended to reconcile Roman factions rather than conduct a campaign of indiscriminate revenge.

Pompey evacuated Brundisium and withdrew to Greece. Caesar was unable to prevent his escape and temporarily concentrated on securing the western provinces and defeating Pompey's forces in Spain.

The campaigns in Hispania and Africa (49 BC)

Caesar recognised that Pompey's position depended upon his provincial armies and commanders as well as his forces in Greece. He therefore moved into Hispania, where Pompey's legates Lucius Afranius and Marcus Petreius commanded substantial forces.

The resulting campaign culminated at Ilerda (modern Lleida) in 49 BC. Caesar's troops faced difficult terrain, shortages of supplies and changing river conditions, but he manoeuvred the Pompeian army into an increasingly difficult position. Rather than risk a costly pitched battle, Caesar gradually forced the opposing commanders to surrender. His success deprived Pompey of an important military base in the western Mediterranean.

The Greek city of Massilia (modern Marseille) had refused to submit to Caesar and supported the Pompeian faction. Caesar left forces under his lieutenants to conduct the siege while he travelled to Hispania. The city resisted for several months before eventually surrendering. Its position was important because of its naval connections and its location on the Mediterranean coast.

Caesar also suffered a serious setback in North Africa. His commander Gaius Scribonius Curio was defeated by the forces of King Juba I of Numidia and the Pompeian commander Publius Attius Varus at the Battle of the Bagradas River. Curio was killed, and Caesar temporarily lost control of the campaign in the province. This defeat demonstrated that Caesar's rapid victories in Italy and Hispania had not eliminated the military strength of his opponents.

The struggle in Greece (48 BC)

Pompey assembled a substantial army in Greece, supported by several prominent senators and experienced Roman commanders. His forces included veterans, provincial contingents and a considerable cavalry advantage. Caesar crossed the Adriatic to confront him, despite the difficulties of transporting his forces and maintaining supplies across the sea.

The two armies manoeuvred around Dyrrhachium (modern Durrës in Albania), where Pompey had established a strong defensive position. Caesar attempted to contain Pompey's army through extensive fortifications and siege works, but Pompey eventually broke through the Caesarian lines and inflicted a serious defeat. Caesar was forced to retreat, and Pompey had an opportunity to pursue him more aggressively than he did. The failure to exploit this victory allowed Caesar to reorganise his army and continue the campaign.

The decisive confrontation occurred at the Battle of Pharsalus in August 48 BC. Pompey possessed the larger army and had a particular advantage in cavalry. Caesar, however, positioned additional infantry to counter Pompey's mounted troops and used his experienced veterans to break the opposing formations. Pompey's army was decisively defeated, and many of his supporters were killed, captured or scattered.

Pompey escaped from the battlefield and fled to Egypt, hoping to obtain protection from the Ptolemaic rulers. Caesar's victory at Pharsalus destroyed the principal military force assembled against him, although resistance continued in other regions.

Egypt and the eastern campaign (48–47 BC)

Pompey arrived in Egypt in September 48 BC, where he expected support from the government of the young King Ptolemy XIII. Instead, members of the Egyptian royal court arranged his murder. Pompey was killed shortly after arriving, an act intended to secure the favour of Caesar when he reached Egypt. Caesar was reportedly displeased by the murder of his former ally and rival.

Caesar's arrival in Egypt drew him into the dispute between Ptolemy XIII and his sister Cleopatra VII. Caesar supported Cleopatra's claim to the throne, and the resulting conflict became known as the Alexandrian War. Caesar and his troops were surrounded in parts of Alexandria and faced a difficult military situation before reinforcements arrived. The struggle eventually ended with the defeat of Ptolemy's forces and the restoration of Cleopatra to the Egyptian throne.

The Alexandrian campaign was particularly important because Caesar's involvement secured a political alliance with Cleopatra and extended Roman influence over the Ptolemaic kingdom. Egypt remained formally a separate kingdom, but its political affairs were increasingly subject to Roman power.

After leaving Egypt, Caesar moved into Asia Minor to confront Pharnaces II, king of Pontus. Pharnaces had taken advantage of the Roman civil conflict to recover territory in the region. Caesar defeated him at the Battle of Zela in 47 BC, restoring Roman authority in the area. The speed of the victory became associated with Caesar's celebrated phrase veni, vidi, vici ("I came, I saw, I conquered").

The African campaign and Battle of Thapsus (46 BC)

Although Pompey himself was dead, a substantial part of the senatorial opposition continued the war. Several of Pompey's supporters had gathered in North Africa under the leadership of Metellus Scipio, with assistance from King Juba I of Numidia. Other prominent opponents, including Cato the Younger, also remained committed to resistance.

Caesar crossed into Africa and conducted a campaign against the combined Pompeian and Numidian forces. The decisive engagement took place at the Battle of Thapsus on 6 April 46 BC. Caesar's army defeated the opposing forces, whose elephants and infantry were unable to withstand the Caesarian attack.

The defeat destroyed much of the organised senatorial resistance in Africa. Metellus Scipio died while attempting to escape, while Juba I also lost his kingdom and subsequently died. Cato withdrew to Utica, where he committed suicide rather than submit to Caesar. His death became a prominent example of republican resistance to Caesar's personal rule.

Caesar returned to Rome after the African victory and celebrated his military successes. Although his opponents had been defeated in several major campaigns, the continuing existence of Pompeian forces in Hispania meant that the war was not yet completely over.

The Spanish campaign and Battle of Munda (45 BC)

The final major phase of the war took place in Hispania, where the sons of Pompey, particularly Gnaeus Pompeius, had gathered the remaining Pompeian forces. The experienced commander Titus Labienus, who had previously served under Caesar during the Gallic campaigns, also fought against Caesar.

The resulting campaign was difficult, with both sides suffering from supply problems and the challenges of operating in the Spanish countryside. Caesar eventually confronted the Pompeian army at the Battle of Munda on 17 March 45 BC. The opposing forces fought fiercely, and Caesar's troops faced considerable pressure before securing victory.

The defeat at Munda destroyed the last major organised Pompeian army. Gnaeus Pompeius was killed during the subsequent pursuit, although his younger brother Sextus escaped and survived to become a significant figure in later Roman conflicts. Labienus was also killed during the fighting. The victory at Munda marked the effective end of the military struggle between Caesar and the principal Pompeian leadership.

Consequences

Caesar emerged from the war as the dominant political and military authority in Rome. He had defeated his principal rivals, gained control of the major provincial armies and secured influence over the eastern Mediterranean and North Africa. His political position was no longer dependent upon the support of a coalition of aristocratic families or the traditional balance of power within the Senate.

Caesar increasingly concentrated authority in his own hands. He was appointed dictator for ten years in 46 BC and was later granted the title of dictator for life (dictator perpetuo) in 44 BC. Although he continued to employ republican titles and institutions, the practical independence of the Senate and the other magistracies was greatly diminished.

Caesar also pursued a policy of clemency, commonly described as Clementia, towards a number of former opponents. Some who had fought against him were pardoned and permitted to resume public life. This policy was intended to reconcile the defeated factions and avoid the cycle of proscriptions and reprisals associated with earlier Roman civil conflicts. Nevertheless, reconciliation remained incomplete, and opposition to Caesar's concentration of power continued.

On 15 March 44 BC, Caesar was assassinated by a group of senators who believed that his personal rule threatened the Roman Republic. The conspirators included Marcus Junius Brutus and Gaius Cassius Longinus. The assassination ended Caesar's dictatorship but did not restore the old republican system. Instead, his supporters and opponents became involved in another series of civil wars, culminating in the rise of Octavian, later Augustus, and the establishment of the Roman Empire.

Historical significance

Caesar's Civil War was a decisive turning point in the history of Rome. It demonstrated that the traditional republican system could no longer contain the ambitions and military power of its most successful generals. The personal loyalty of veteran armies had become a major political force, and the Senate was increasingly unable to resolve disputes without the threat or use of military violence.

The conflict also revealed the international extent of Roman political power. Its campaigns crossed the Mediterranean, involving the provinces of Hispania, the Greek world, Egypt, North Africa and Asia Minor. Local kingdoms and political factions were drawn into what had originated as a struggle between leading Roman politicians.

The war did not formally abolish the Roman Republic. Its offices, laws and institutions continued under Caesar and subsequently under Augustus. However, Caesar's victory made the restoration of the earlier republican balance of power increasingly unlikely. The political order that emerged under Augustus was the result of the further civil wars following Caesar's assassination, rather than the immediate result of the Battle of Munda alone.

Sources and historical accounts

The principal contemporary narrative of the early campaigns is Caesar's own Commentarii de Bello Civili (The Civil War), consisting of three books. Caesar's account is particularly valuable because he was a leading participant and describes military operations, negotiations, political decisions and the conduct of his commanders. However, it is also a political defence of his actions and must be read with an awareness of his position as one of the principal belligerents.

The campaigns in Egypt, Africa and Hispania are described in separate works traditionally associated with the Caesarian corpus: the Alexandrian War, the African War and the Spanish War. These accounts were not written by Caesar himself, and their authorship is uncertain. They provide important additional evidence for the closing stages of the conflict.

Other important ancient sources include the biographies of Caesar and Pompey by Plutarch, the imperial biographies of Suetonius and the histories of Appian and Cassius Dio. The letters and speeches of Cicero are also valuable for understanding the political divisions and constitutional disputes that preceded and followed the outbreak of war.

Modern studies include Adrian Goldsworthy's military history of the conflict and his biography of Caesar, as well as Robert Morstein-Marx's examination of Caesar's political relationship with the Roman people and the causes of the civil war.

See also

• Gaius Julius Caesar
• Pompey the Great
• First Triumvirate
• Roman Republic
• Battle of Pharsalus
• Battle of Thapsus
• Battle of Munda
• Roman civil wars
• Augustus