Battle of Issus

Battle of Issus

Following his victory in the May 334 BCE Battle of the Granicus River, Macedonian king Alexander III (Alexander the Great) marched south, continuing the liberation of the Greek coastal cities of Asia Minor. He met real opposition only at Miletus, which he captured following a brief siege.

Alexander then took the momentous decision of disbanding his fleet of some 160 triremes. He kept only the Athenian detachment, to serve as transports and provide hostages, and a squadron in the Hellespont. With the Persian fleet of more than 400 triremes dominating the eastern Mediterranean, Alexander could not hope to win a sea battle, and maintaining the fleet was expensive. His commanders opposed this decision. The Persians might now easily cut off the army in Asia Minor and prevent both its resupply and its return to Macedonia and Greece. They could also raid Greece and stir up revolts against Alexander there. Alexander, however, believed that his men would fight harder knowing that retreat was not possible. He also seems to have profoundly distrusted his Greek allies, so much so that he was prepared to risk his entire campaign rather than entrust its safety to a Greek fleet.

Mosaic depicting Macedonian king Alexander III’s victory over Persian king Darius III at Issus in 333 BCE. The youthful Alexander (left) leads the charge of retreating Persian troops commanded by Darius (right). It was Alexander’s second defeat of a Persian army. (Jupiterimages)

Alexander told his generals that he intended to move against the Persian fleet from the land instead, taking the Persian and Phoenician naval bases along the eastern Mediterranean coast. During 334–333 he conquered much of the coast of Asia Minor. Alexander’s early military successes owed much to his reputation for mercy, justice, and toleration. It certainly helped his cause that his rule brought improved administration, lower taxes, and public works projects. The only difficult operation occurred at Halicarnassus, where the defenders were led by the Greek mercenary Memnon. Alexander took the city after a siege.

While Alexander secured the remaining coastal cities, Persian king Darius III now loosed Memnon, his only first-class general, against Alexander’s lines of communication. However, Memnon soon took sick and died. Darius was gathering yet another army for another military test with the invader when he learned that Alexander had moved south into Syria. Darius therefore moved before he was fully ready. Crossing the Amarnus Mountains, he positioned his forces behind Alexander, cutting off his line of communications. With the potentially hostile cities of Phoenicia to the south, Alexander had no choice but to turn and fight.

The two armies came together at Issus in early November 333 BCE (possibly November 5). The numbers are in dispute. Darius probably had more men, perhaps as many as 100,000 (Macedonian reports of 600,000 are complete propaganda). Alexander had only 30,000 men. Darius positioned his army on the narrow coastal plain on the north side of the steep-banked Pinarus River, a front of about three miles. This meant that only part of his force could engage at any one time. Largely untrained troops held the Persian left and right; Darius placed archers to their fronts to buttress them. In the center of the Persian line were the 2,000 Royal Bodyguards, the elite force in the army. Darius was with them in a great ornamental chariot. As many as 30,000 Greek mercenaries were on either side of the Royal Bodyguards, while Persian cavalry anchored the far right flank on the Gulf of Issus. If the Persians could at least hold, Alexander’s days would be numbered.

Alexander arrived before the Persian line in late afternoon. The Persian cavalry screen that had been south of the Pinarus masking Darius’s dispositions and intent now withdrew across the river. Alexander halted to reorganize his line. Seeing Darius massing his cavalry on his right flank near the seashore against the Macedonian left wing under Parmenio, Alexander shifted his Thessalonian cavalry there, placing it behind the phalanx so as to conceal their movement. He sent a mixed force of light-armed troops to deal with a Persian detachment in the hills that had worked its way behind his right wing. He also detached cavalry from the center to strengthen his right wing, but the Persians on his far right made no attempt to attack and were soon routed. Alexander then recalled most of his troops sent against them, leaving only 300 cavalry to protect his far right flank.

Having completed his dispositions, Alexander resumed the advance. His forces were also on a three-mile front. He halted just out of bowshot, hoping that the Persians would attack. As he occupied a strong prepared defensive position, Darius understandably refused. Alexander then ordered his own men forward. Determining that the infantry on the Persian left was the weak part of the enemy line, Alexander had his Macedonian heavy cavalry (the Companions) on the right of his line.

Battle was joined when the Persian archers let loose a volley of arrows said to be so thick that they collided with one another in air. The archers then withdrew back into the mass of infantry as Alexander led the Companions in an assault against the light infantry on the Persian left. It almost immediately broke.

The Macedonian attack in the center did not go as well. The men had difficulty getting across the river and then encountered a steep bank and stake palisades placed by the Persians. Desperate hand-to-hand fighting ensued, pitting the Macedonian infantrymen against equally tough Greek mercenaries. Alexander meanwhile rolled up the Persian left.

Alexander then shifted his cavalry to strike the rear of the Greek mercenaries and the Royal Bodyguards in an effort to kill or capture Darius. Alexander was wounded in the thigh during the fighting, some reports say by Darius himself. Wounded, the horses on Darius III’s chariot suddenly reared and bolted. Darius managed to control them but, in danger of capture, shifted to a smaller chariot and fled the field.

Things were not going well for Alexander elsewhere, however. The Macedonian center was hard-pressed, as were the Thessalonians on the left, by the Persian heavy cavalry. Alexander therefore had to break off his pursuit of Darius. Alexander swung his right wing into the Persian army’s Greek mercenaries from the flank, rolling them up. When the men of the Persian heavy cavalry saw this and learned of the flight of Darius, they too decamped. Retreat became rout. Alexander pursued but was forced to break this off due to darkness.

Persian losses may have been as high as half of the force, or 50,000 men, while Alexander reported some 450 dead. Among the captives were Darius’s wife, mother, and two daughters. The loot included some 3,000 talents in gold. Alexander also recovered Darius’s royal mantle and insignia, which he had stripped off in flight.

The Battle of Issus was a glorious victory for Alexander, but it was not decisive. More than 10,000 Greek mercenaries escaped and would form the nucleus of
yet another army. Darius still lived, and as long as this was the case the fight would continue.


Green, Peter. Alexander of Macedon, 356–323 B.C.: A Historical Biography. Berkeley: University of California Press, 1991.

Hammond, Nicholas G. L. Alexander the Great: King, Commander, and Statesman. 3rd ed. London: Bristol Classical Press, 1996.

Sekunda, Nick, and John Warry. Alexander the Great: His Armies and Campaigns, 332– 323 B.C. London: Osprey, 1988.