The Battle of Thermopylae: How 300 Spartans stood against the massive Persian army

In 480 BC, an alliance of Greek city-states led by Sparta faced an enormous invading Persian army at the pass of Thermopylae.

The Persians, led by King Xerxes, had a numerical advantage of over 2:1 and expected an easy victory. 

However, while the Persians did eventually defeat the defenders, it was certainly not easy.

The Greeks held off the Persians for three days before finally being overrun. This battle has been cited as one of history's most famous last stands. 

In the early fifth century BC, the Persian Empire was at the height of its power. The Persians had conquered most of Asia Minor and were now eyeing expansion into Europe.

In order to do this, they needed to first deal with the Greek city-states who had supported the Ionian cities in Asia Minor in a revolt against Persia.

The Persians began by targeting Athens, one of the most important Greek city-states.

The Athenians managed to defeat an initial Persian invasion at Marathon in 490 BC.

Following the defeat at Marathon, the Persian king Darius had died and was succeeded by his son, Xerxes.

Xerxes was determined to complete his father's work and crush the Greeks once and for all.

In 480 BC, he assembled the largest army that had ever been seen and set out to conquer Greece.

In 480 BC, the Persian army, led by King Xerxes, invaded Greece by crossing the Bosphorus Strait and marching south towards Athens.

When news of the Persian invasion spread, the various city-states quickly banded together in an alliance led by Sparta.

The Spartan king Leonidas was chosen to lead the Greek army against the Persians. 

When word of the oncoming army reached Greece, the first move was for around 8,000 hoplites (including 300 Spartans and 2000 helots from the Peloponnese, 700 Thespians, 400 Thebans, and 1000 Phocians) to take up position at the Vale of Tempē near Mt. Olympus to engage with the invaders.

However, when it became apparent that the invading Persian force was significantly larger than the combined Greek forces, they retreated southward to find a better location for the battle.

Leonidas chose to make his stand at Thermopylae. Thermopylae was a strategic location, because the Persians had to travel along a road through this region in order to get to Athens.

At Thermopylae, the road became a narrow pass that was bordered by steep mountains on one side and the sea on the other.

For 1.5 kilometres, the Persian army would become vulnerable, as they had to march in a narrow line, sometimes no wider than a wagon.

The limited space would allow the Greeks to nullify the Persian numerical advantage and their cavalry.

Also, the Greeks repaired an old wall halfway along the pass that would further obstruct the Persian army's ability to advance along the road.

Leonidas appears to have not expected a victory against the Persians but hoped to fight a delaying action.

This would simply slow the Persian advance in order to give the Greek cities in the south time to evacuate to safety.

Since they expected to eventually lose, the Greek force at Thermopylae was reduced to around 6000 men, including 300 Spartans, 2,120 Arcadians, 1,000 Lokrians, 1,000 Phokians, 700 Thespians, 400 Corinthians, and 400 Thebans, plus others. 

The Spartans only had 300 hoplites because they knew that the fight would be end in defeat and only wanted soldiers who had living sons who could replace them after their deaths.

The rest of the Greek soldiers were allowed to return home.

The Greek cities also sent a fleet of ships to the coast of Artemesium on Euboea's northern coast, 40 nautical miles from Thermopylae.

Their main goal was to prevent the Persian navy from sailing down the coast towards Athens.

The Persian army was a massive force. The exact number of Persian soldiers is a matter of historical debate, with Herodotus claiming that it was 2.5 million strong, while modern estimates are much lower, generally around 100,000 to 150,000.

The core of the army was made up of Immortals, an elite group of soldiers who were hand-picked by the king and given special training.

The Persian infantry was armed with short spears and wicker shields, while the cavalry was armed with bows and lances.

Persian war tactics usually relied upon an initial volley of arrows to do as much damage to enemies as possible before sending a huge number of infantry in waves to overwhelm the remaining defenders.

However, the heavy hoplon shields used by the Greeks were large and thick enough to negate the effectiveness of the arrows, while the restricted space created by the narrow path reduced any benefit of larger numbers of soldiers.

In the summer of 480 BC, the Persian army arrived at Thermopylae and demanded that the Greeks surrendered. Leonidas refused, and the battle began. For three days, the Greeks held off the Persians. 

On the first day of battle, the Persians advanced against the Greeks, but they were quickly pushed back by Leonidas and his men. 

The Persian army was unable to break through the Greek defenses, and they suffered heavy casualties.

This was primarily due to the differences between the infantry types on both sides.

The Greek hoplites were heavy infantry, armed with long spears and heavy shields, while the Persians were light infantry, armed with short spears and wicker shields.

On the second day of battle, Xerxes became impatient and ordered his troops to attack again.

The Persians were again unable to break through the Greek defenses. 

Xerxes consulted with his generals and decided to send in his elite Immortals on the second day.

The Immortals were a group of hand-picked soldiers who had undergone special training. They were considered to be some of the best warriors in all of Persia. 

The Greeks were outnumbered and outmatched, but they fought bravely against the Persians.

However, the Immortals were no more effective than the previous Persian troops. Despite their better training, they were armed with the same weapons and armour as regular troops, so were unable to cause significant numbers of Greek casualties.

The second day of battle ended with little progress being made by the Persians and increasing numbers of deaths among their troops.

On the evening of the second day, a local Greek man named Ephialtes came to the Persian camp and offered to show Xerxes' soldiers a way around the narrow pass. The Persian king was hesitant, but he eventually agreed. 

That night, Ephialtes led a group of Persian soldiers through a secret path that went around the narrow pass. 

Leonidas had been aware of this mountain path, and he had sent the 1000 Phocians to keep watch over it.

The Phocians put up a fight before being outflanked and forced to retreat. Finally, by daybreak, the Persian force arrived behind the Greek line and prepared to attack them from the rear.

When Leonidas was aware of this development, he ordered the majority of the Greek soldiers to leave if they wanted to, which many did.

However, he stayed behind with 300 Spartans to hold off the Persian army and buy the retreating Greeks as much time as possible.

The Thespians, Thebans, and probably the 2000 helots also chose to stand and fight to the end with the Spartans.

By dawn on the third day of battle, a small force of Persians had been able to flank the Greeks.

The Spartans were then attacked from the front and from behind by the Persian army. The remaining Greeks intended to fight to the death.

The Greeks charged out of the pass and met the Persian forces head-on, to maximise the number of enemies they could kill. 

They fought with their spears until they were all shattered, and then continued to fight with their short swords. Leonidas was killed in action and the Greeks attempted to recover his body.

However, when the Persian Immortals advanced, the remaining Greeks had to retreat to a nearby hill where they prepared to make their last stand.

It was at this time that the remaining Thebans chose to surrender to the Persians, but the other Greeks did not.

Seeing his remaining enemies trapped on a hill with nowhere to flee, Xerxes decided to avoid the huge death tolls from the previous days.

He ordered his Persian archers to fire successive volleys of arrows until the last of the Greeks were killed. 

With the death of the last Greek defender, Xerxes ordered that the defensive wall at Thermopylae to be torn down, and he continued his march towards Athens.

The Battle of Thermopylae was a resounding Persian victory, but it was not the only battle occurring at that time.

The Greeks had already sent their navy to block the narrow straits at Artemisium in order to prevent Xerxes' huge fleet of around 700 ships supplying the land army with food and water. 

The Greeks had a fleet of around 270 triremes under the command of the Spartan admiral, Eurybiades, and the Athenian commander, Themistocles. 

Prior to the battle, the Persians had lost around 400 ships in two successive storms along the coast of Euboea.

The Greeks were protected from these storms, as they were sheltered in harbours.

When the two fleets finally fought each other over three days, neither side was able to gain an advantage. The fighting lasted all day and by dusk, both sides had suffered roughly the same number of losses.

A council of war was held among the Greeks to decide what to do. At the meeting, news was received about Leonidas' death and the defeat at Thermopylae. 

The Greek commanders decided that there was nothing more to be gained at Artemisium and they retreat back to Athens that night.

The Battle of Thermopylae was a significant military victory for Persia. However, it was not the crushing victory that Xerxes had hoped for.

The Persian army was delayed long enough for the Greeks to prepare their defenses at the narrow pass at Corinth and to evacuate the people from the city of Athens. 

Kleombrotos, Leonidas' brother took over command of the Spartan army and prepared to defend the isthmus of Corinth from an expected Persian attack.

This never eventuated. Themistocles, an Athenian politician and general, prepared his city for war by using his fleet to ship the Athenians to the island of Salamis, across the bay from Athens.

Xerxes' army reached Athens shortly after the retreating Greek navy departed. The city was defended by a small number of remaining men and was quickly captured by the Persians.

As a way of punishing the Greeks, Xerxes ordered that Athens be burnt to the ground.

Although they had been defeated at Thermopylae, the Greeks went on to defeat Xerxes' army at Salamis later that year.

This victory marked a turning point in the war, and ultimately led to the Greeks defeating the Persians at the Battle of Plataea in 479 BC.

The Battle of Thermopylae was a significant event in ancient history. It demonstrated the power of a well-trained and disciplined fighting force against a much larger and better-equipped enemy.

The Spartans' bravery and sacrifice also inspired other Greeks to resist the Persian invaders. 

The Battle of Thermopylae is remembered as one of history's most famous last stands.

The Spartans' heroic defense against an overwhelming enemy has inspired people for centuries.

Today, it is still studied in military academies around the world as an example of effective leadership and strategic planning.