Battle of Pydna: How the Romans Ended the Macedonians

The Battle of Pydna was the second major clash between the Macedonian phalanx and the Roman legion. The first, Cynoscephalae, in 197 BCE, saw the phalanx outmaneuvered and defeated by the more flexible Roman legions. The defeat stripped Macedonia of its long-held power over Greece, but the kingdom survived to fight another day. That day came on June 22nd,168 BCE as once again, the Macedonian and Roman armies faced each other in the heart of Macedonia. This time, the very existence of the kingdom was at stake.

There was no particular incident that caused the Third Macedonian War (171-168 BCE). Instead, it stemmed from Rome’s distrust of Macedonia and its King, Perseus (179-168 BCE), and the risk he posed to its dominance of the eastern Mediterranean.

Our sources paint an almost wholly negative picture of Perseus’ character and reign, but some of this, at least, is propaganda used to justify Rome’s war. Taking the sources as face value, Perseus was deceitful, cowardly, bent on war, unwilling to part with money, and responsible for the murder of his brother. For some Romans, Perseus was suspect even before coming to the throne as he was blamed for the death of his brother Demetrius, who was liked in Rome.

Roman historians later claimed that Perseus inherited both a hatred of Rome and plans for war from his father. In reality, one of Perseus’ first acts was to maintain the peace, and he was frequently in contact with the Roman senate, even making several attempts to negotiate during the war. Both Philip V (221-179 BCE) and Perseus did rebuild the Macedonian army but in the circumstances, this seems more a matter of prudent and essential policy than plans for war.

Part of the rebuilding process saw Perseus attempt to restore relations with several Greek states and form alliances with the kingdoms of Bithynia in Asia Minor and the Seleucids in Syria. Perseus’ moves beyond Macedonia’s borders were limited and careful and were allowed to pass by the Romans at the time. Still, there was perhaps a fear that a resurgent Macedonia would upset the system of influence and alliances set up following the Second Macedonian War (202-197 BCE).

In this atmosphere of distrust, it did not take much to provide an excuse for war. A Roman ally, Eumenes II of Pergamon (197-159 BCE), played on Roman fears and told the senate that Perseus was a threat and was even preparing to invade Italy. The senators readily believed such stories, and when Eumenes claimed Perseus tried to have him killed outside Delphi they seized the opportunity for war. After a quarter century of uneasy peace, Rome sent its legions back to Macedonia.

As the Romans prepared for war in 172-171 BCE, Perseus stood largely alone with few allies. Attempts to rebuild relations with the Greek states to the south failed due to fear of Rome and lingering resentment at Macedonia’s long rule over Greece. Only some parts of the Boiotian communities in central Greece were willing to align themselves with Perseus. To the north and west, there were some hopes of winning over the lands of Epirus and Illyria. Any Macedonian allies there would threaten Rome’s ability to send troops and supplies.

This left Perseus to face the Romans with his own army. The careful rebuilding of Macedonia by Philip V and Perseus gave some grounds for hope. As the war began, the Macedonian army was said to be over 40,000 men strong. It had perhaps not been this strong since the glory days of Philip II and Alexander the Great almost two centuries previously.

At the core of this army was the famous Macedonian heavy infantry phalanx. The phalanx was a densely packed body of pikemen welding an 18ft pike known as a sarissa. The length of the sarissa allowed five spear points to project out in front of the first rank of soldiers, presenting the enemy with a moving wall of spears. Massed in formations sixteen men deep, the phalanx was virtually unapproachable and unstoppable once it got moving. This formation had conquered the Persian Empire and created and maintained the Hellenistic kingdoms. However, the Romans had defeated the phalanx at Cynoscephalae by taking advantage of the superior flexibility of their legions.

Macedonia’s preparations bore fruit in the war’s early years. Perseus defeated a Roman force at the Battle of Callinicus in 171 BCE and won over parts of Epirus and Illyria. Roman attempts to invade Macedonia were meanwhile largely unsuccessful. These early years, however, were inconclusive. Perseus could perhaps hope that so long as he avoided defeat, the Romans may eventually tire of the war and look to a negotiated peace as he tried to do on a number of occasions but to no avail. Just like his father’s war, the matter would have to be settled by a battle between the phalanx and the legion.

In 169 BCE, the war arrived in Macedonia as Roman forces managed to cross the passes of Mt Olympus. Once over the mountains, however, their campaign lost momentum. Perseus reportedly panicked at the unexpected news and lost the opportunity to confront the Romans as they emerged from their trek tired and hungry. On the other hand, the Romans reached Macedonia but lacked supplies and so a stalemate ensued. Perseus fortified a position along the river Elpeus in a narrow stretch of land between the mountain and the sea, blocking further progress.

The sub-par performance of the legions led to the election of Lucius Ameilius Paullus to the consulship and command in Macedonia for 168 BCE. At 60 years old, and as a father and son of generals, he was seen as the man to reinvigorate the Roman war effort. Upon arriving at the front in the early summer of 168 BCE, he immediately reimposed discipline and looked for ways to bring on a decisive battle.

The problem for Paullus was that Perseus’ defensive position along the river was too strong to tackle head-on. The Romans did have the advantage of controlling the sea around Macedonia. The fear of a Roman landing along the coast made Perseus detach several thousand troops from his army, reducing the numbers available to confront Paullus. Despite this advantage, the Roman command chose a more surprising approach. A small Roman force marched toward the coast as if they were to attempt to get around the Macedonian position by sea. However, they secretly turned around and hiked up a path around the mountains. Emerging unexpectedly, this force swept aside any Macedonian guards and got behind Perseus’ defenses.

Suddenly, sitting between two Roman forces, Perseus was forced to retreat towards the coastal city of Pydna. As the Macedonians retreated, Perseus let slip another opportunity. The two Roman forces had marched a long way to link up with each other. When they did so, they were exhausted and faced Perseus’ fresher army across a narrow plain. But Perseus hesitated, allowing Paullus to prepare a camp and slowly retreat into its safety. The battle would not be fought this day. As both sides settled down for the night, an eclipse of the moon provided an ominous portent.

The two armies were likely similar in size at around 30-35,000 each. Perseus commanded a phalanx of around 21,000, with the rest of the army made up of elite Macedonian light infantry and cavalry, Thracian allies, and small contingents of Greek allies and mercenaries. Paullus could count on around 26,000 Roman and Italian legionnaires with further Italian and Greek allies. The Romans also had the advantage of a small group of elephants provided by Rome’s North African allies. Expecting to face elephants, Perseus had prepared an anti-elephant unit with spiked helmets but this experiment appears to have failed as they had no impact on the battle (Livy 44.41).

Though a battle was by now unavoidable and probably desired by both sides, what actually occurred on June 22nd was unplanned. Johstono and Taylor (“Reconstructing the Battle of Pydna” 69, 2022) describe Pydna as a “meeting engagement,” a battle in which the two sides clash haphazardly rather than as the result of careful deployments and tactics. According to our sources, it all started with a single horse or mule. The animal broke away from the Roman side and went towards the river used by both armies for water. In trying to retrieve the animal, a skirmish broke out, drawing in more and more troops. Though it was by this time mid-afternoon, late to start a battle, both armies were soon streaming out of their camps and closing in on each other.

To be effective, the phalanx needed to lower their sarissas and advance together as one mass across a level field. In this position, they presented the army with a wall of spearheads that they could not approach. Being 20 ft long the sarissa could kill the bravest soldier before they had a chance of coming to grips with the man holding it. So intimidating was the sight of an advancing Macedonian phalanx that even Paullus admitted his fear (Plutarch, Life of Ameilius,19.1).

The phalanx faced a problem when it became disjointed or was attacked on its undefended flank or rear. The Macedonian pikemen carried only a light shield and a short sword or dagger. If they had to turn around or fight individually, the sarissa became useless, leaving each soldier extremely vulnerable. This lack of flexibility was fatal at Cynoscephalae when the Romans were able to peel off small groups from their legions and attack the rear of the phalanx. A quarter of a century later, a similar story played out at Pydna.

Impossible as it was to attack a wall of spears from the front, the Romans instead started pushing into the gaps in the phalanx that opened up as the Macedonians advanced. According to the Roman historian Livy (44.41), rather than the two rival battlelines clashing head-on, the fighting took the form of multiple small battles as the phalanx became disjointed in the face of multiple Roman attacks. Lacking cohesion, the phalanx was a collection of vulnerable individual soldiers rather than an unstoppable mass. Matters quickly got worse for the Macedonians. A Roman charge led by the elephants overwhelmed the Macedonian left flank by the stream where the battle began.

In the face of these attacks, the Macedonian army crumbled in little more than an hour. So swift was the disaster that Perseus and his cavalry had not even managed to join the battle but instead were compelled to flee. With the Romans having broken up and overwhelmed the entire Macedonian line the battle now degenerated into a massacre. The Macedonians who tried to flee to the coast were trapped between the sailors of the Roman fleet that killed men in the sea and the elephants that now lined the shore and trampled the survivors. As many as 20,000 are said to have died, with 11,000 captured (Livy 44.42). This is probably an exaggeration as those numbers would represent almost the entire Macedonian army, but by the evening of June 22nd, 168 BCE, there was no Macedonian army left to speak of. In contrast, the Romans reported only around 100 dead.

With no army left to defend it, Macedonia quickly fell to the Romans. Perseus tried to escape, but having been trapped on the island of Samothrace he was compelled to surrender. He ended his days as a prisoner in Italy, having been paraded through Rome in Paullus’ triumphal procession.

Having fought three wars against the kings of Macedonia, the Romans decided it was time to put an end to the centuries-old monarchy. The kingdom of Macedonia was divided into four separate states which were free but had to pay tribute to Rome.

The Battle of Pydna did not finally end the Macedonian wars, but it confirmed Rome’s dominance of the eastern Mediterranean. Having destroyed the last great Macedonian army in one afternoon, the supremacy of the legion over the phalanx was now beyond doubt.