Battle of Pharsalus

Battle of Pharsalus

Following the Punic Wars the Roman republic was on its deathbed. Slavery had concentrated wealth in the hands of a few, and latifundia (great estates worked by slaves) took the place of small freehold farms. Landless peasants flocked to Rome, where candidates for public office bought their votes. Increasingly, the senators came to think of the state as their private property. The army too became corrupt. Ordinary citizens raised private armies. No longer were soldiers drawn into the military from a sense of duty; instead, they joined the military as a means of making a living. These professional soldiers recognized neither the Senate nor the law but rather only the authority of their generals.

Key figures arose in the ambitious millionaire Licinus Crassus and the arrogant young Gnaeus Pompeius, known as Pompey. Both had established their military reputations under Lucius Cornelius Sulla, who had defeated King Mithradates of Pontus and made himself dictator in Rome in 81 BCE, only to retire three years later. As consuls, Crassus and Pompey soon demonstrated their independence of Senate control. Pompey commanded Roman forces against Mithradates, who was again at war with Rome. An outstanding general, Pompey during 68–62 defeated Mithradates, captured Judea, and annexed the city-states of Syria. In 60 Pompey allied himself with the aristocratic Gaius Julius Caesar and Crassus in an unofficial partnership known as the First Triumvirate (60–51 BCE), cemented by Pompey’s marriage to Caesar’s daughter Julia.

The division of spoils under the First Triumvirate made Caesar consul in 59, followed by a military command for 5 years (later increased to 10 years) in Illyricum (Yugoslavia) and in Gaul on both sides of the Alps (France and northern Italy). Pompey received the governorship of Spain for 5 years, which he exercised by proxy from Rome. Pompey’s wife Julia died in 54, and a group of senators talked Pompey into a breach with Caesar to limit the tenure of Caesar’s command in Gaul and prevent him from again becoming consul. In 53 Crassus was killed in fighting in Parthia across the Euphrates, and the First Triumvirate was over. The next year amid increasing civil unrest, Pompey became sole consul where there had always been two, a precedent for emperors. Caesar’s term in Gaul came to an end in 49. If he wanted to run for consul again, he would have to give up his military command. When Pompey would not do the same, Caesar decided on military action.

Caesar and Pompey (and their legions) now fought for control of the Roman state. Outnumbered by Pompey’s potential force, Caesar relied on boldness. Announcing that “the die is cast,” he broke Roman law by bringing his legions across the Rubicon River into Italy proper. Caesar quickly occupied Italy, while Pompey withdrew to the Balkans. Following rapid expeditions to subdue Corsica and Sardinia, Caesar sailed to Spain and secured the surrender of two armies loyal to Pompey at Ilerda and Gades (Cádiz). He also took Massilia (Marseilles) in southern Gaul. Caesar then returned to Italy and had the Senate declare him dictator.

In January 48 after assembling sufficient shipping for half of his army, Caesar pursued Pompey into the Balkans. Caesar sailed across the Adriatic to Dyrrachium (Durrës), where Pompey was building his forces, and laid siege to it. When Caesar’s subordinate Mark Antony (Marcus Antonius) arrived in March with reinforcements, Pompey sallied from Dyrrachium and drove Caesar away. Leaving a strong detachment at Dyrrachium, Pompey then cautiously pursued Caesar into Thessaly in northern Greece while another army loyal to Pompey secured Macedonia. Caesar hoped that by threatening to attack this latter force he could draw Pompey into an attack. Pompey, who now had Caesar heavily outnumbered and could thus wear him down, was reluctant to risk his advantage in pitched battle but was apparently goaded into it by advisers who convinced him that Romans would want to see Caesar crushed in actual combat.


Pompey and Caesar and their armies came together at the Plain of Pharsalus, near Cynoscephalae in Thessaly, in August 48. Both armies were camped next to the Epineus River a few miles from each other. Each day the armies deployed, only to return to camp; gradually Caesar moved his forces closer to Pompey, hoping to entice him into an attack. Pompey had some 45,000 infantry and 7,000 cavalry, while Caesar commanded only 22,000 infantry and 1,000 cavalry. Caesar’s left flank rested on the steep banks of the Enipeus River. His right flank was the weak point. Here his cavalry was outnumbered 7 to 1. Caesar formed his troops in three lines, but he held back six cohorts, about 2,000 men, in the so-called fourth line to cover his right rear. He extended the intervals between his cohorts to match the frontage of Pompey’s line, which was drawn up in normal formation. Caesar’s third line, as usual, was a reserve to the other two. Caesar took his own position with the fourth line to the right rear.

Pompey refused to allow his men to attack, holding them in a compact mass to break Caesar’s charge. Pompey thought that enemy javelins would be less effective if the men were stationary rather than running forward. Caesar therefore ordered an attack on Pompey’s stationary force. Caesar’s men rushed forward, javelins leveled. When they saw that Pompey’s men were not running out to meet them, Cesar’s veterans knew immediately to halt their charge so as not to wear themselves out. After a short interval they resumed the charge, hurling their javelins and drawing their swords. Pompey’s side threw their own javelins and then resorted to their swords.

At the moment of the infantry impact Pompey launched his cavalry on his left flank, supported by archers and slingers, against Caesar’s horsemen. Although Caesar’s cavalry fought well, they fell back from Pompey’s vastly superior numbers. Then Caesar wheeled out with his six reserve cohorts. They charged with such force that Pompey’s cavalry were scattered. This left Pompey’s archers and slingers exposed, and they were overwhelmed and slain. Caesar then turned the fourth line against the left flank of Pompey’s more numerous army and drove it in from the rear.

At the same time Caesar ordered forward his third line, which had been inactive to this point. This fresh force and the fourth line attacking from the rear set Pompey’s army to flight. Caesar would not allow his men to stop to plunder and instead pressed the pursuit. Pompey escaped with only a handful of followers, reaching the coast and sailing for Egypt. Caesar’s superior military leadership and bold innovation had carried the day against a capable yet unimaginative commander who had failed to divine Caesar’s intentions. The Battle of Pharsalus cost Pompey 15,000 killed and 24,000 prisoners; Caesar lost 230 killed and perhaps 2,000 wounded. Greece and Asia now declared for Caesar.

In Egypt, Pompey’s remaining troops mutinied, and he was murdered. Caesar then campaigned in Egypt and Asia Minor in the company of the beautiful 22-yearold Cleopatra, whom he confirmed as queen of Egypt. Cleopatra bore Caesar a son, Caesarion. Caesar returned to Rome and, in further lightning wars, crushed Pompey’s sons in North Africa in 46 and in Spain in 45. In 46 Caesar was appointed dictator for 10 years. The republic was over.


Caesar, Julius. War Commentaries of Caesar. Translated by Rex Warner. New York: New American Library, 1960.

Grant, Michael. The Army of the Caesars. New York: Scribner, 1974. ———. Julius Caesar. New York: M. Evans, 1992.

Suetonius. The Twelve Caesars. Translated by Michael Graves. London: Penguin, 1957.