Battle of Ipsus

Fought in 301 BCE on a plain in Phrygia, in the interior of modern Turkey, Ipsus was the decisive battle of the long wars between Alexander's successors. Antigonus the One-Eyed, the most powerful of them, and his son Demetrius faced an alliance of Seleucus, Lysimachus and Cassander. Antigonus was killed, his realm was divided, and with it went the last serious attempt to hold Alexander the Great's empire together under one ruler.

By 315 BCE Antigonus controlled most of Alexander's Asian lands, which alarmed the other successors. They fought him in one war that ended in a compromise peace in 311 BCE, and Seleucus then defeated him in a struggle for Babylonia. Antigonus and his son nevertheless remained formidable. Demetrius won Athens in 307 BCE, destroyed Ptolemy's fleet off Cyprus the next year, besieged Rhodes and, in 303 and 302 BCE, drove Cassander's garrisons out of much of Greece. When Antigonus refused Cassander anything short of surrender, Cassander and Lysimachus sought help from Ptolemy and Seleucus.

In 302 BCE Lysimachus crossed the Hellespont and overran much of western Asia Minor, reinforced by Macedonian troops sent by Cassander. Antigonus marched north from Syria to meet him, but Lysimachus refused battle, slipping away from two fortified camps until winter ended the campaign. Antigonus recalled Demetrius from Greece. Meanwhile Seleucus marched west from the eastern provinces and wintered in Cappadocia, and Ptolemy made a brief raid into Syria before withdrawing to Egypt on a false report of an Antigonid victory.

The only full account of the battle is Plutarch's, written roughly four centuries later, and his figures are approximate. He gives Antigonus some 70,000 infantry, 10,000 cavalry and 75 war elephants. The allies had perhaps 64,000 infantry and, by modern estimates, around 15,000 cavalry, together with 120 scythed chariots and some 400 to 480 elephants, most of them brought by Seleucus from India, where he had received them from the Mauryan ruler Chandragupta.

The fighting seems to have opened with the elephants of both sides colliding in front of the lines. Demetrius then led the best Antigonid cavalry against the allied horse under Seleucus's son Antiochus and routed it, but he chased the fugitives too far. When he tried to return, he found a wall of allied elephants, perhaps 300 of them, blocking his path; horses will not readily face elephants, and he could not get through. How the allies managed this manoeuvre, whether from a planned reserve or by improvisation, is unclear.

With its right flank now bare, the Antigonid infantry was threatened by allied cavalry, including mounted archers, who rode around it without charging. Plutarch says Seleucus hoped to persuade them to change sides, and many did defect or flee. Antigonus stayed in the centre waiting for his son, until he was surrounded and killed by javelins.

Demetrius escaped to Ephesus with some 5,000 infantry and 4,000 cavalry, but found Athens closed to him and his Greek allies falling away; he left Pyrrhus of Epirus to look after his interests in Greece. The victors shared out Antigonus's lands. Lysimachus took western Asia Minor, Seleucus most of the remaining Asian territory, strengthening what became the Seleucid Empire, and Ptolemy kept Egypt. The Hellenistic world would now be one of rival kingdoms rather than a single empire.

Our 300 BCE map shows the kingdoms of the successors as they stood immediately after Ipsus.