Battle of Issus
- Macedonians and their Greek Allies, led by Alexander. With about 5,000 cavalry, 26,000 infantry.
- Persians under Darius III with some 30,000 Greek mercenaries, 60,000 Persian infantry and 30,000 Persian cavalry. (NOTE: these numbers were given by the ancient sources, principally Arrian and Curtius, who were notorious for inflating Persian numbers to make Alexander's victories seem that much more extraordinary)
The battle took place south of the ancient town Issus, which is close to present-day Iskenderun, Turkey, on both sides of a small river called Pinarus. At that location the distance from the gulf of Issus to the surrounding mountains is only 2.6 km, a place where Darius could not take advantage of his superiority in numbers.
Speculation on the location of the Pinarus has been raging for over 80 years. Older historians believed it to be the Deli Tchai river, but historians N.G.L. Hammond and A.M. Devine have made convincing claims that the Pinarus is actually the Payas River, the latter using eye-witness examination of the river, which may not have drastically changed since antiquity. Their evidence is based off of Callisthenes' accounts of the measurements of the battlefield and distances marched by both armies in the prelude to the battle and distance given by Diodorus after the battle.
While Alexander was in Tarsus he heard of Darius massing a great army in Babylon. If Darius were to reach the Gulf of Issus he could use the support from the Persian fleet under Pharnabazus still operating in the Mediterranean Sea, thus easing his supply and possibly landing troops behind the enemy. Alexander kept his main army at Tarsus but sent Parmenion ahead to occupy the coast around Issus. In November, Alexander received reports that the great Persian army had advanced into Syria, to a town named Sochi. Alexander decided to mass his scattered army and advance south from Issus through the Pass of Jonah.
Darius knew that Parmenion held the Pass of Jonah and thus chose a northern route of advance. The Persians captured Issus without opposition and killed all the sick and wounded that Alexander had left behind. Now Darius found out that he had placed his army behind the Macedonians and had cut their supply lines. He then advanced to a good defensive position along the river Pinarus and waited for Alexander to come to him.
There is much debate as to the motives of Alexander and Darius preluding Issus. A strong and convincing modern perspective, based on Curtius, is that Darius was forced to move camp to terrain that favored Alexander because Alexander was fighting defensively due to a recommendation by his war councel and Parmenion. Darius' large army could not be supported in the field during winter and his cities in Phoenicia were already in unrest at the arrival of Alexander. Darius was forced to move his large army to a small battlefield which overwhelmingly favored Alexander's smaller force.
Alexander was waiting for Darius to come south around the Amanus Mountain range because the pass Darius would have used, the Belen Pass, was much closer to Sochi and offered the quickest access to the area Alexander defended. Alexander was waiting 10 miles to the west of the Belen Pass at Myriandrus to spring a trap on Darius as he crossed through the Belen Pass or through the Pillar of Jonah if he moved north, where Darius' army would be disorganized and disjointed in the narrow crossing. Darius instead moved north from Sochi and around the mountains, emerging behind Alexander's position and on his supply and communication lines. Thus Alexander was forced to march to Darius, who had caught him off guard in a large flanking maneuver. This gives the illusion that Darius was the one acting defensively, since Alexander was forced to march to him.
The Macedonians advanced through the Pillar of Jonah. Alexander led his Companion cavalry on the right flank and he set his Thessalian Greek allied cavalry on the left of the Macedonian phalanx with Parmenion in command.
Darius formed his line with his heavy cavalry concentrated next to the coast on his right, followed by the Greek mercenary phalanx (historian A.M Devine places them at a strength of 12,000, comparable to the Macedonian phalanx). Next to the Greek phalanx Darius spread his Persian infantry, the Cardaces, along the river and into the foothills, where they wrapped around to the other bank and threatened Alexander's right flank (the formation resembled gamma, Γ). Arrian gives an inflated figure of 20,000 to these troops. Darius positioned himself in the centre with his best infantry, the Greek mercenaries, and his royal cavalry guard. According to some historians, like P. Stratikis, he was trying to "copy" the Hellenic battle formation of the Battle of Granicus.
The Persian cavalry charged Parmenion and the allied cavalry across the river to open the battle. Alexander's left wing once again became the crux of the battle, like at Gaugamela two years later, where Parmenion held the wing long enough against superior Persian numbers so that Alexander could make his calculated cavalry strike against Darius and break the Persian army. The Hypaspists led by Alexander, on foot, delivered an assault during this time across the riverbed on the Cardaces and managed to punch a hole through the Persian line.
Alexander then mounted a horse at the head of his Companion Cavalry and led a direct assault against Darius who fled from the battlefield. This caused the Persians to abandon their positions in full rout. The Macedonian cavalry pursued the fleeing Persians for as long as there was light. There was significant carnage after the battle due to the massive, unorganzied retreat and the pursuing Macedonians. Arrian mentions Ptolemy I as saying that Alexander and his bodyguards, while pursuing Darius, came upon a gap which they effortly crossed on the bodies of dead Persians.
The battle of Issus was a decisive Macedonian victory and it marked the beginning of the end of Persian power. It was the first time the Persian army had been defeated with Darius present.
Depictions of the battle
The battle of Issus was illustrated (according to the Roman writer Pliny) by a Greek painter, Philoxenus of Eretria, in the late fourth century BC. This painting does not survive, but a mosaic representing the battle, perhaps after this earlier Greek painting, was found in Pompeii in the House of the Faun. The mosaic is now in the National Museum of Naples and is dated first century BC; see: Alexander Mosaic