The Battle of Thermopylae was fought in 480 BC during the Greco-Persian Wars and was the first important event of the second Persian invasion under Xerxes I. It stands out as one of the greatest military deeds and a shining symbol of courage and determination in the face of overwhelming odds; a granite stone of values in the foundations of Western Civilization.
As Xerxes’ I army, under the command of Mardonius, advanced southward on their way to Athens, the Greek troops instigated a council meeting. Some Peloponnesians suggested withdrawal to the Isthmus and blocking the passage to Peloponnesus. They were well aware that the Persians would have to go through Athens in order to reach them there. The Phocians and Locrians, whose states were located nearby, became indignant and advised defending Thermopylae and sending for more help. Leonidas and the Spartans agreed to defend Thermopylae.
The Thermopylae was a mountain pass 100 meters wide, west of the Gulf of Malis, and about 150 km north of Attica. Thermopylae means "hot gates" because of the hot springs near by. As the Persians entered the pass, they sent a mounted scout to reconnoiter. The Greeks allowed him to come up to the camp, observe them, and depart. When the scout reported to Xerxes the size of the Greek force and that the Spartans were indulging in calisthenics and combing their long hair, Xerxes found the reports laughable. Xerxes did not know that it was an Spartan custom to adorn their hair when they were about to risk their lives.
Xerxes remained incredulous, finding it unbelievable for such a small army to contend with his own. Plutarch informs that he then sent emissaries to the Greek forces. At first, he asked Leonidas to join him by offering the kingship of all Greece. Leonidas answered: "If you had any knowledge of the noble things of life, you would refrain from coveting others’ possessions; but for me to die for Greece is better than to be the sole ruler over the people of my race." Then Xerxes asked him more forcefully to surrender their arms. To this Leonidas gave his noted answer: "Come and get them".
Leonidas had under his command 300 Spartans, 900 helots, 700 Thespians, 1,000 Phocians, and 4,000 other Greek allies, against an enemy force of 200,000 Persians plus 10,000 elite troops of Xerxes’ personal guard. Despite their extremely disproportionate numbers, Greek morale was high. Herodotus writes that when Dienekes, a Spartan soldier, was informed that Persian arrows would be so numerous as "to block out the sun", he responded with a characteristically laconic remark, "So much the better; we shall fight in the shade."
Xerxes waited four days for the Greek force to depart before starting the attack. On the fifth day he sent Medes and Cissians, along with relatives of those who had died ten years earlier in the battle of Marathon, to take the Greek prisoners and bring them before him. They soon found themselves in a frontal assault. The Greeks had camped on either side of the Phocian wall. The wall was guarded and the Greeks fought in front of it.
The Persian king, Xerxes I, having taken the measure of the enemy, threw his best troops into a second assault on the same day: the Immortals, an elite corps of 10,000 men. They also failed to open the pass even though they were flogged by their leaders to press on. On the second day Xerxes sent another 50,000 men to assault the pass, but again they failed. Xerxes at last stopped the assault and withdrew to his camp, totally perplexed. The Persians suffered terribly from their lack of protective armour and wickerwork shields. Besides, the Greek hoplites that defended the pass were in their element, as Greek warfare revolved around close-combat and the average hoplite was far better equipped and trained for hand-to-hand fighting than his Persian adversary.
His failure to defeat the Greeks threw Xerxes into a terrible rage and he had some of his commanders executed. But late on the second day of battle, as the Persian king was pondering what to do next, he received a windfall: a Malian Greek traitor named Ephialtes informed him of a goat path around Thermopylae and offered to guide the Persian army. Xerxes sent his commander Hydarnes to flank the pass with 40,000 men under his command.
The path led from east of the Persian camp along the ridge of Mt. Anopaea behind the cliffs that flanked the pass, then it forked with one trail leading to Phocis and the other down to the Gulf of Malis at Alpenus. Leonidas had stationed the 1,000 Phocian volunteers on the heights to guard that path.
Their first warning of the approach of the Persians at daybreak was the rustling of oak leaves. The Persians were amazed to see the Greeks hastily arming themselves. They feared that they were Spartans, but, enlightened by Ephialtes, they proceeded by firing "showers of arrows" at them. The Phocians retreated to the crest of the mountain to make their stand and defend their city which was behind the mountain range, but the Persians took the left branch of the path that led behind the main Greek force.
Although he was in a dangerous and hopeless position, Leonidas resolved to continue his defence of the pass, but he first ordered most of the Greek forces to leave to protect the cities they came from. Amongst those that remained were 300 Spartans, 700 Thespians, 400 Thebans and 900 helots. Knowing he had no hope of winning, Leonidas advanced his phalanx further out into the pass. The Greeks fought until their spears were broken before using their xiphos, which the Spartans used with great dexterity. They withstood waves after waves of Persians assaults, parrying and thrusting in deep their swords as blood and entrails came out of gaping wounds that turned the barren ground into the red sticky mud of glory. Leonidas was killed in one of these attacks and a vicious struggle followed as the Greeks and Persians fought over his body.
Arrows continued to rain down on the Greek position for hours. The few survivors were eventually overwhelmed in a final squalid slaughter. The body of Leonidas was beheaded and crucified. His bones would not return to Sparta for many years.