How the Battle of Ipsus Determined the Fate of Alexander’s Empire | History Hit

How the Battle of Ipsus Determined the Fate of Alexander’s Empire

Image Credit: History Hit

By 304 BC, the Wars of Alexander the Great’s Successors had been raging intermittently for some 16 years. Prominent warlords had risen and fallen – including some of Alexander’s leading adjutants. But the great climax of these wars was fast approaching. This bloody battle would overshadow all before it: the Battle of Ipsus.

On one side was the extraordinary father-son team of Antigonus and Demetrius, commanding an empire stretching from the Hellespont to Judaea. On the other side was a grand coalition of rival kings, desperate to topple the great Antigonid behemoth. They included warlords such as Seleucus, Lysimachus, Ptolemy and Cassander. This is the story of the Battle of Ipsus, and why it mattered.

Demetrius heads to Greece

Following his failure to capture the city of Rhodes, Demetrius set sail for Greece as ordered by his father. For the past two years, Cassander, King of Macedon, had been fighting a war against the city of Athens. Although initially successful, by 304 BC Athenian resistance was crumbling. Cassander had defeated their fleet and now blockaded Athens by sea and by land.

Just as Athens appeared certain to fall, news reached Cassander that would alter his plans completely: at Aulis, Demetrius had landed his army, which was greatly reinforced since the debacle at Rhodes. Fearful of being surrounded, Cassander quickly broke off the siege and headed back towards Macedonia. During the retreat, the wily Demetrius intercept his forces near Mount Kallidromo. In the ensuing engagement, 6,000 of Cassander’s Macedonian soldiers deserted to his cause.

‘Commander of the Greeks’

Rather than pursuing Cassander, Demetrius turned his attention to affairs in central Greece. In the Peloponnese, the influence of Cassander and Ptolemy was still formidable. Reluctant to leave his forces exposed, Demetrius launched a full-scale campaign in the region.

The result was an overwhelming success. Both Cassander and Ptolemy’s holdings in the Peloponnese were removed completely. Demetrius now aimed at consolidating his new gains in Greece. Not only did he declare the cities free, as decreed by his father, but Demetrius made one other critical move to further Greek unity for his cause.

At the Isthmus near Corinth, Demetrius was proclaimed ‘Commander of the Greeks’, following in the footsteps of both Philip II and Alexander. Nearly all the mainland Greek cities south of Thessaly, except for Sparta, were incorporated into this grand alliance and contributed troops to the young Antigonid’s army. With this act, Demetrius’ control of Greece was secured.

Demetrius then married the Molossian princess, Deidameia and thus allied himself with the Epirote League to the West. His power in Greece unassailable, Demetrius could now look north towards his goal: Macedonia.

The successor kingdoms before the Battle of Ipsus, 303 BC.

Image Credit: Public Domain

Cassander sues for peace

Cassander had been watching Demetrius’ actions from Macedonia with growing alarm. An invasion by the young Antigonid, he realised, would only be a matter of time. Cassander therefore sent envoys to Antigonus in Syria offering peace. Antigonus, however, had no intentions of stopping; he replied that there would be no peace unless Cassander gave up all his belongings to Demetrius and the Antigonid kingdom.

On hearing Antigonus’ haughty reply, Cassander naturally refused. War, he realised, was inevitable and he now called for aid from his neighbouring Macedonian ruler in Thrace.


Until then, Lysimachus role in the previous wars had been minimal, having been preoccupied with the lingering barbarian threat across the Danube River and with unrest within his own kingdom. Now however, he travelled to Pella to aid Cassander.

From there, they dispatched further envoys to further strengthen the alliance against Antigonus – to Ptolemy in Egypt and Seleucus in Asia. The Grand Coalition against Antigonus was taking shape. On hearing of this new alliance, Ptolemy quickly accepted and prepared his army. Seleucus’ reply would take longer to reach them.

The Seleucid-Mauryan war

At the time, Seleucus was far away in India, campaigning against the Mauryan King Chandragupta. The war did not go well for Seleucus. After suffering a defeat against his Indian foe they concluded a treaty where Seleucus was forced to give up his most eastern lands to the Mauryan Empire.

In return, friendship was agreed; but importantly, Seleucus received a staggering 500 Indian War elephants from the Mauryan king.

Not only were Indian War Elephants both larger and stronger than their African counterparts, but their handlers were some of the most skilled in the world. Seleucus had such a large elephant division that Demetrius famously mocked his opponent as ‘the Master of Elephants’.

Image Credit: Hannibal's army crossing the Rhône, by Henri Motte, 1878 / Public Domain

The march begins

With these beasts in tow, Seleucus began to march his army back to the heartlands of his empire in Mesopotamia.

Not long after he departed India, the envoys from Cassander, having ridden on horseback all the way from Macedonia, finally reached Seleucus’ army and informed him of events in the West. Committing everything to the campaign, Seleucus accepted the call and commenced his long journey west towards Asia Minor.

The first move

Meanwhile, the first move against Antigonus had been made. Two armies, under the command of Lysimachus and Cassander’s best general, Prepelaus had launched a surprise attack on Antigonus, invading Asia Minor and quickly capturing much Antigonid territory in Western Asia Minor. Cassander himself marched to Thessaly to defend against any attack from Demetrius.

Antigonus rallies his men once more

Antigonus had been residing at his capital of Antigonia when he heard of Lysimachus’ unexpected invasion. Although now eighty years old, he prepared to lead his army to war once more. Arriving in Asia Minor in the autumn of 302 BC, Antigonus pursued Lysimachus’ forces around the Anatolian plateau. Eventually, winter descended and both forces retired to await a resumption of the fighting in the Spring.

It would be then, however, that news reached Antigonus that would turn his plans upside down. In record time, Seleucus and his great army, having crossed the mountains of Armenia, had arrived in Asia Minor. If more information on his march survived, we would likely regard it as one of the most fascinating military achievements in history – eclipsing that of even the great Hannibal Barca.

Pressing on, Seleucus soon reached Lysimachus’ army at Heraclea and there united their forces in opposition to Antigonus and Demetrius.

Seleucus led the Royal Hypaspistai during Alexander’s Persian campaign.

Image Credit: Public Domain

Ptolemy turns tail

Ptolemy at that time was besieging the Antigonid city of Sidon in Syria. Yet he would advance no further, as a false rumour had reached his ears that the armies of Seleucus and Lysimachus had been crushed by Antigonus. Ptolemy was unnerved and returned to Egypt with his army.

The call for aid

Back in Asia Minor, Antigonus sent word to Demetrius, ordering him and his army to cross over from Greece and join him for the impending showdown. Demetrius duly obeyed. Having landed at Ephesus, he quickly recaptured many of the cities on the coast that had defected to Lysimachus; he then joined his father at Celaenae. With both sides substantially reinforced, they now awaited the spring and the climactic battle that would occur.

Deployment at Ipsus

As the winter subsided, on a plain near the town of Ipsus in Phyrgia, the two great armies collided. Antigonus had in his army 70,000 infantry, mostly heavily-armed pikemen battle-hardened from many previous campaigns. These he deployed in the centre, along with the best mercenaries money could buy.

On his right wing, Antigonus placed Demetrius, in charge of 5,000 of their finest cavalry, among whom was the young, exiled Molossian king. A man called Pyrrhus. On his left, Antigonus deployed the remaining 5,000 of his horsemen; and in front of his line, Antigonus placed his 75 war elephants, with light infantry stationed close-by protecting the beasts.

Seleucus and Lysimachus’ army was similarly large. In their centre, they deployed their own infantry, 64,000 strong. Many were armed in the Macedonian manner, although Seleucus’ infantry also consisted greatly of various Asian levies, hailing from his kingdom’s heartlands in Mesopotamia, as well as from Bactria and the Hindu Kush.

They divided their cavalry equally on both flanks, placing 7,500 on each wing. As for his elephants, Seleucus deployed a portion of them in front of the army line. The rest he kept in reserve. Seleucus also had a number of scythed chariots, but it appears unlikely he used them.

Diagram of the Battle of Ipsus.

Image Credit: Public Domain

The Battle of Ipsus: 301 BC

The battle commenced with an elephant charge by both sides, with the infantry following up close behind. Demetrius ordered his elite cavalry wing to charge their opposing horsemen (which were under the command of Seleucus’ son, Antiochus).

Quickly overwhelmed, Antiochus and his cavalry retreated from the fight and Demetrius, caught up in the thrill of a cavalry chase, hastened his force in pursuit. Meanwhile, the phalanxes had engaged and very quickly the experience and skill of Antigonus’ foot began to push those of Lysimachus and Seleucus back. An Antigonid victory looked likely.

The critical moment

It would be then, however, that Seleucus used his ‘secret weapon.’ Having finally called off the pursuit, Demetrius reorganised his cavalry and started to return to the battlefield, intending to crash into the enemy infantry line from behind.

Seleucus however had anticipated the move. As soon as he saw Demetrius returning, he deployed his 300 war elephants in reserve to block the young Antigonid’s path.

Demetrius’ cavalry was blocked and powerless – their mounts unwilling to charge directly into elephants; and Seleucus now issued the fateful order.

He ordered their light cavalry, equipped with javelins and bows, to wheel-round onto Antigonus’ now-exposed right wing and hail a rain of missiles into the dense Antigonid phalanx from its weak flank.

He (Seleucus) did not actually charge upon them (the Antigonid phalanx), but kept them in fear of a charge by continually riding around them, thus giving them an opportunity to come over to his side. And this was what actually came to pass.

Plutarch, Demetrius 29.3

Death of a king: who won the Battle of Ipsus?

Outflanked and unprotected, Antigonus’ army soon crumbled. Antigonus himself remained on the field until the end. Even as the enemy forces approached, this octogenarian never gave up hope that Demetrius would return and turn the tide of battle.

Contained by Seleucus’ great beasts, Demetrius did not come. Never losing confidence in his son, Antigonus perished in a shower of enemy javelins. At multiple times in the past 20 years he had controlled great swathes of Alexander the Great’s empire. Now he was no more.

In late 321 BC, a carefully-constructed plot was put into operation that would spark years of bloody conflict between rival warlords. The target of the operation was Alexander the Great’s elaborate funeral carriage and the conqueror’s talismanic corpse housed within.
Watch Now

What was the significance of the Battle of Ipsus?

Antigonus lay dead on the field and his son, despairing, fled to Greece. From there, Demetrius and his descendants would continue to fight, eventually taking control of Macedonia for the next 100 years.

Antigonus had been so close to achieving the nigh-impossible in reuniting Alexander’s Empire. He would be the last man who seriously attempted to achieve such a dream. With his death, a new epoch began. Alexander’s former empire was to be forever fragmented between his successors, never to be reunited.

The victors of Ipsus enjoyed the spoils of war, dividing Antigonus’ vast lands in Asia Minor and Syria between them. Yet almost straight away, dividing these battle-won territories stirred up new quarrels. In Syria, immediately, the seeds for a new dispute between Seleucus and Ptolemy arose. Each would claim control, with neither giving ground. War once again loomed.

The anti-Antigonid coalition proved crucial in defeating Antigonus. But ss soon as he was dead, co-operation gave way to fear and enmity. Ipsus was just the beginning: conflict between these newly secured Hellenistic Kingdoms would proliferate for decades.

Tags: Alexander the Great

Tristan Hughes