On the 5th of November 333 BC, Alexander the Great and his army met the Persian forces of Darius III in Battle at "Issus".
The clash between these two great armies would be one of the most decisive in history.
Background
Before we get into the battle itself, let's take a look at the background leading up to it.
In 334 BC, Alexander invaded Persia with an army of 30,000 Macedonians and Greeks.
The Macedonian king wanted to destroy the Persian Empire, which was ruled by Darius III at that time.
Alexander claimed that his invasion was in response to Persia's invasion of Greece, around 150 years earlier, all the way back in 480 BC.
Once Alexander's army had entered Asia Minor by crossing the Hellespont, they defeated one of Darius' armies at the Battle of Granicus River in 334 BC.
Following his victory, Alexander marched across Asia Minor, towards Darius' capital city of Persepolis.
At that point, Darius now considered Alexander as a genuine threat to the existence of his empire and so he marched west to meet him in battle personally.
Cat and mouse
When Alexander heard that Darius was marching an army towards him, he thought that the deciding battle of his campaign was close at hand.
The Macedonian king began organising his forces.
Alexander marched his forces southward from the city of Gordium, through the Cilician Gates, and arrived at the coastal town of Issus.
Alexander decided to use this town as a base of operations, to bring in food and supplies for his army during the campaign.
He also left a number of his soldiers who were wounded and sick at Issus to recover.
Alexander then marched the rest of his army south, along the coastline, since he had received word that Darius' army was there.
However, the rumour was incorrect, and Darius was actually to the east. The Persian army marched to Issus, hoping to engage Alexander.
When the army arrived, they only found a hospital full of the injured men that had been left behind.
The ancient sources state that Darius tortured and executed the Macedonian soldiers.
Even when he granted some mercy and let them live, he still punished them for invading his empire by cutting off their right hands.
This act would serve as a further incentive to Alexander's army to defeat the Persians.
Manoeuvring
When Alexander received word that his enemy was now north of him, had taken over his supplies, and had killed many of the wounded soldiers, Alexander was outraged.
He quickly ordered his army to turn around and march back towards Issus.
Darius also learned of where Alexander really was and marched his forces out from Issus.
The Persian king hoped that he would have enough time to choose the field of battle: a place that would play to his army's strength while highlighting the Macedonian weaknesses.
The two armies met at a small river called Pinarus. Darius had chosen the battlefield carefully.
On one side was a marsh, and on the other were hills. This would make it difficult for Alexander's cavalry to attack and give Darius' infantry an advantage.
Darius had between 50,000 to 70,000 soldiers with 10,000 Greek mercenaries. Darius placed himself in the centre of his army, in a chariot.
In comparison, Alexander had around 24,000 soldiers and 4,000 cavalry. That means that the Persian army may have outnumbered Alexander's forces by as much as three to one.
Alexander, on the other hand, actually enjoyed a significant benefit from the battlefield, because not only did the larger number of troops limit Darius's mobility, it provided more room for Alexander to manoeuvre his own troops.
The Battle of "Issus"
In the centre of Darius' army were the famous Persian Immortals: an elite force of soldiers who were said to never lose a battle or retreat from combat.
On the right flank of the Persian army were amassed all of the Persian cavalry.
Darius hoped their overwhelming numbers would easily crush the smaller number of Alexander's cavalry on the opposite side.
The Macedonian king placed his infantry in the centre of his battle line and divided his cavalry into both of the wings.
One division, on the right, under the command of Alexander himself, would take on Darius and the centre of his army.
The other division, on the left, under the guidance of Parmenion, was to engage Darius' right flank and tie them down.
The battle began with the Persian cavalry charging across the river and engaging the Macedonian line.
Parmenion knew that he had to hold the Persians back for as long as possible, no matter the cost. In the centre, the Macedonian infantry attempted to march across the river and engage the Persian infantry.
Unfortunately, not only was the river crossing difficult, the Macedonians had to fight Darius' Greek mercenaries, which proved too difficult to break.
The Macedonians were forced back.
On the Macedonian right wing, Alexander initially led his infantry across the river to engage the Persian left flank.
The attack was successful and this opened up a hole in the Persian line. Then, Alexander led a cavalry charge through it and headed directly for Darius' chariot.
When Darius saw the imminent threat that Alexander and the approaching Macedonian cavalry posed to him, he ordered his chariot to turn around and flee.
Despite chasing hard, Alexander was not able to catch up with the Persian king.
Instead of continuing to pursue Darius, Alexander ordered his cavalry to turn around and attack the Persian lines from behind.
Being attacked from the front and behind caused a huge number of casualties among the Persians.
So, without their leader and facing certain defeat, the Persian army fled. An estimated 40,000 Persian soldiers were killed in the battle, in comparison to around 500 Macedonians.
Aftermath
The Persian defeat was so total, and they had fled from the battlefield in such a hurry that they left behind their camp and all their supplies.
This was a clear victory for Alexander and his army. Not only had he decisively defeated the largest army in the world, but he had also captured Darius' family, including his wife, children, and mother.
However, Darius asked for the return of his family, promising Alexander half of his kingdom, which was rejected.
Instead, Alexander challenged him to face him again on the battlefield.
Alexander in Egypt
After Alexander's victory at Issus, he marched south to Persian-controlled Egypt. Alexander wanted Egypt because he knew that it was a wealthy nation and he wanted to add its resources to his empire. He conquered Egypt in 332 BC.
The Egyptians were happy to see Alexander since they had been oppressed by the Persians for many years.
They welcomed him as a liberator and gave him gifts of gold and silver.
In return, Alexander made Egypt a part of his empire and named the city of Alexandria after himself.
He also placed Egyptians in high positions within his government and allowed them to keep their religion and customs.
Alexander's visit to Siwa
While in Egypt, Alexander visited the Temple of Amun-Ra at Siwa Oasis. The temple was home to the Oracle of Amun-Ra, who was said to be able to answer any question.
When Alexander asked the Oracle if he was indeed the son of Zeus, the Oracle replied that he was indeed a god and not a mortal man.
This response pleased Alexander and solidified his belief that he was destined to conquer the world.
After his visit to the Temple of Amun-Ra, he returned to Memphis, where he held a cultural and sports festival for both Egyptians and Greeks.
He wanted this to be an example of cooperation between the two ancient civilisations.
After six months in Egypt, Alexander left to chase Darius once more in 331 BC. Alexander would not see Egypt again.
Only after his death would his body return to the city he named after himself, to be buried.
Summary
The Battle of Issus would be one of Alexander's most important victories during his campaign against Darius III and the Persian Empire.
It not only increased Macedonian morale, but it also boosted recruitment as more men joined Alexander's cause.
