Battle of the Granicus

Following the Persian defeat at Plataea in 479 BC, the Greeks counterattacked and liberated the cities of Asia Minor, but after 460 BC fell to fighting amongst themselves, granting the Persian Empire not only a breathing space but also opportunities to manipulate Greek politics to keep Greece divided. The temporary Greek unity following the Peloponnesian War was undermined by Persian gold and diplomacy, bringing to a halt Agesilaus' attempt to conquer Asia Minor. By 386 BC Persian influence was so pervasive that the Peace of Antalcidas of that year was largely dictated by the Persians.

                           
               

The prevalence of Persian influence was dispelled by the rise of Macedon. From 356 to 346 BC, Philip II led Macedon to the position of hegemon over Greece, uniting Hellas through the League of Corinth. Then he died, the victim of domestic intrigue and, allegedly, Persian gold.

His successor Alexander III, faced immediate revolts by Illyrian tribes and defections from the League of Corinth. However, using the fine army he had inherited, together with his own superb generalship, he rapidly subdued the Illyrians, defeated Thebes and re-established the League of Corinth. Two years into his reign, he was ready to invade Asia in the first of a series of campaigns which would bring down the Persian Empire.


His army was based on the native Macedonian hetairoi  (Companions), armed with the long xyston instead of the customary javelins, and the pezhetairoi (Foot Companions, i.e. the phalanx), armed with the very long sarissa. Supplementing these were the hypaspists, elite pikemen who could use the javelin and the sarissa, and the sarissophoroi, also called prodromoi (vanguard), who could similarly use the sarissa and javelins whether mounted or on foot. In addition, Alexander fielded the best of the Thessalian cavalry and the elite of the Thracian, Paeonian and Odrysian cavalry (the latter two were Thracians but are distinguished separately in our sources). These probably used the xyston, as they are all described as acting in a shock role; the Paeonians also scouted, like the sarissophoroi.

Alexander's army was a combined arms army, and in addition to the above troop types contained javelinmen, primarily Agrianes, archers, both Cretan and Macedonian, and slingers. These missile troops were mainly used to provide shooting support for the cavalry, softening up opponents before the Macedonian cavalry charged into melee. This would not be possible at the Granicus so Alexander instead mingled them with the Macedonian cavalry where they could injure and unseat Persian cavalrymen concentrating upon fighting their Macedonian counterparts.

Facing him at the Granicus was a Persian army under the Rhodian mercenary general Memnon, the most talented of the Greeks in Persian service. Diodorus' description of this army as containing 10,000 cavalry, 100,000 Asia Minor infantry and 5,000 Greek mercenaries appears to be a year out of date; this was probably the force fielded against Parmenio's advance expedition while Philip II was still alive, but by 334 BC Memnon had been promoted from commanding the Greek mercenaries to commanding the whole army, and had made significant changes, sending home the near-useless levies, increasing the number of cavalry and recruiting may more Greek mercenaries. The result, as described by Arrian, was an army of 20,000 cavalry and almost the same number of Greek mercenaries. This was encamped, awaiting Alexander. Memnon had wanted to retire ahead of Alexander's advance, burning crops and destroying supplies as he went, in order to deprive Alexander's army of supply. The Persian nobles, whose satrapies this plan would devastate, unanimously disagreed, so Mamnon had selected a camp and battle position on the Granicus river. His cavalry were camped next to the river, making it easy to water their horses, while his infantry were camped in Greek fashion on the nearest high ground, which had a commanding view of the area.

The the Macedonian army came in sight. As the Persian cavalry gathered at the riverbank to watch, and the Greek mercenaries assembled on their hilltop to view the Macedonian arrival, Memnon and his officers were all together, viewing and assessing the opposition. Although the Macedonians were approaching in order of battle, infantry in the centre and cavalry on the wings, Memnon did not see any of the League of Corinth Greek contingents, which were following with the baggage, so assumed Alexander would wait for them to catch up before attempting a battle. For this reason, he issued no orders and did not attempt to deploy his army.

Alexander saw that the Persian leaders were all gathered together in one place, while the Persian cavalry was standing around on the riverbank like a crowd of spectators and the Greek mercenaries had made no move to descend from their hilltop. Alexander's instinct was to attack now, without waiting, catching the Persians undeployed, out of formation and out of command. But first he needed to know what the other side was thinking, and with this in mind he asked Parmenio what he would do. Parmenio's answer was to wait for the remainder of the army and attack on the morrow. Parmenio represented the essence of contemporary military judgement and experience, and what Parmenio thought was what any experienced general would be thinking. Hence, knowing that his attack would be unexpected, Alexander determined to fight an immediate battle.

Alexander had marched his army in order of battle. This allowed him to launch an immediate attack with minimal preparation. The preparation involved assigning the cavalry squadron of the day, under its officer Socrates, to lead the attack across the Granicus. Supporting Socrates were Amyntas' battlegroup consisting of the sarissophoroi, the Paeonians and a 'taxis' of 'pezhoi', a formation of infantry, type unspecified. These would the light infantry (psiloi) subsequently referred to by Arrian as helping the Macedonian cavalry in their fight against the Persians. Alexander followed Amyntas' and Socrates' force with the main body of the Companions, and the rest of his army advanced in echelon, crossing the Granicus slowly but surely.

Meanwhile, Amyntas and Socrates had been halted by Persian missiles and blocked by Persian cavalry as they attempted to struggle up the riverbank. Alexander and his Companions now caught up and, in good order because of being shielded by the advance guard, began to press the Persians back from the riverbank with their long xystons and the assistance of their light infantry, who were almost certainly Agrianians, fierce-fighting hillmen who were Alexander's best javelinmen. 

Alexander had aimed his attack directly at the cluster of Persian generals. Memnon managed to send Omares with orders to bring up the Greek mercenaries, but several of the other Persian generals preferred to stay and fight Alexander, or were unable to leave for their commands owing to the swiftness of Alexander's attack. While Alexander and his closest Companions cut down Persian generals, the Persian army was left leaderless and without a battle plan.

More of Alexander's army were crossing the river and making contact, while Alexander himself led a successful push to struggle up the riverbank, driving back the Persian cavalry facing him and breaking his xyston in the process. He then noticed an alarming development: one of the Persian generals, Mithridates, a relative of Darius, King of Kings, had assembled a command of cavalry into a fighting formation and was leading it to counterattack the tenuous Macedonian hold on the riverbank. Alexander, seeing his men still struggling, resolved to deal with this threat himself; calling for a new xyston, he received one and promptly used it to charge and kill Mithridates, whereupon Mithridates' men failed to charge.

Meanwhile, Omares had managed to get the Greek mercenaries moving, and in doing so lost the Persians the battle. The mercenaries poured down the hill behind the Persian centre, unnerving the Persian cavalry in that sector, who were watching the Macedonian phalanx cross the river in impressively good order to their front. It was at this juncture that Rhoesaces, who should have been leading them, decided to attack Alexander himself and managed to land a blow on his helmet before Alexander slew him. Spithridates, attempting the same, was intercepted and disabled by Cleitus the Black before he could complete his stroke.

With three leaders dead in quick succession, the Macedonian Companions forcing them back from the riverbank, the Macedonian phalanx crossing the river and Omares' Greek mercenaries descending on their rear, the Persian cavalry broke and ran. Alexander let them go in order to concentrate on the still-battleworthy Greek mercenaries, who hurriedly retreated back up the hill and formed an all-round defence. Alexander was incensed at these 'traitors against Greece' who fought for Persian pay, and rejected their attempt to surrender. His troops closed in from all sides, and apart from 2,000 whom his troops took prisoner, the mercenaries were soon dead.


Alexander had won an impressive victory at very little cost. Although significant numbers of Macedonians had been wounded (Alexander visited them all after the battle), those killed amounted to only 130 or so, about three quarters of whom were cavalry. The Persians had lost their entire inventory of Greek mercenaries, about a thousand cavalry, three generals, their pride and their only hope of defending Asia Minor. Alexander had begun the spectacular career of conquest that would see him overthrow what was then the largest empire in recorded history.

   Written by Belisarius and edited by Patrick