First Persian invasion of Greece in the context of "Battle of Thermopylae"

The second Persian invasion of Greece (480–479 BC) occurred during the Greco-Persian Wars, as King Xerxes I of Persia sought to conquer all of Greece. The invasion was a direct, if delayed, response to the defeat of the first Persian invasion of Greece (492–490 BC) at the Battle of Marathon, which ended Darius I's attempts to subjugate Greece. After Darius's death, his son Xerxes spent several years planning for the second invasion, mustering an enormous army and navy. The Athenians and Spartans led the Greek resistance. About a tenth of the Greek city-states joined the 'Allied' effort; most remained neutral or submitted to Xerxes.

The invasion began in spring 480 BC, when the Persian army crossed the Hellespont and marched through Thrace and Macedon to Thessaly. The Persian advance was blocked at the pass of Thermopylae by a small Allied force under King Leonidas I of Sparta; simultaneously, the Persian fleet was blocked by an Allied fleet at the straits of Artemisium. At the famous Battle of Thermopylae, the Allied army held back the Persian army for three days, before they were outflanked by a mountain path and the Allied rearguard was trapped and annihilated. The Allied fleet had also withstood two days of Persian attacks at the Battle of Artemisium, but when news reached them of the disaster at Thermopylae, they withdrew to Salamis.

Hoplites (/ˈhɒplaɪts/ HOP-lytes) (Ancient Greek: ὁπλῖται, romanized: hoplîtai [hoplîːtai̯]) were citizen-soldiers of Ancient Greek city-states who were primarily armed with spears and shields. Hoplite soldiers used the phalanx formation to be effective in war with fewer soldiers. The formation discouraged the soldiers from acting alone, for this would compromise the formation and minimize its strengths. The hoplites were primarily represented by free citizens – propertied farmers and artisans – who were able to afford a linen or bronze armour suit and weapons (estimated at a third to a half of its able-bodied adult male population). Some states maintained a small elite professional unit, known as the epilektoi or logades ('the chosen') because they were picked from the regular citizen infantry. These existed at times in Athens, Sparta, Argos, Thebes, and Syracuse, among other places. Hoplite soldiers made up the bulk of ancient Greek armies.

In the 8th century BC, Greek armies started to adopt the phalanx formation. The formation proved successful in defeating the Persians when employed by the Athenians at the Battle of Marathon in 490 BC during the First Greco-Persian War. The Persian archers and light troops who fought in the Battle of Marathon failed because their bows were too weak for their arrows to penetrate the wall of Greek shields of the phalanx formation. The phalanx was also employed by the Greeks at the Battle of Thermopylae in 480 BC and at the Battle of Plataea in 479 BC during the Second Greco-Persian War.

The Battle of Marathon took place in 490 BC during the first Persian invasion of Greece. It was fought between the citizens of Athens, aided by Plataea, and a Persian force commanded by Datis and Artaphernes. The battle was the culmination of the first attempt by Persia under King Darius I to subjugate Greece. The Greek army inflicted a crushing defeat on the more numerous Persians, marking a turning point in the Greco-Persian Wars.

The first Persian invasion was a response to Athenian involvement in the Ionian Revolt, when the city-states of Athens and Eretria each sent a force to support the cities of Ionia in their attempt to overthrow Persian rule. The Athenians and Eretrians had succeeded in capturing and burning Sardis, but they were then forced to retreat with heavy losses. In response to this raid, Darius swore to burn down the two cities that had aided the failed revolt. According to Herodotus, Darius had his bow brought to him and then shot an arrow "upwards towards heaven", saying as he did so: "Zeus, that it may be granted me to take vengeance upon the Athenians!" Herodotus further writes that Darius charged one of his servants to say "Master, remember the Athenians" three times before dinner each day.

The Battle of Artemisium or Artemision was a series of naval engagements over three days during the second Persian invasion of Greece. The battle took place simultaneously with the land battle at Thermopylae, in August or September 480 BC, off the coast of Euboea and was fought between an alliance of Greek city-states, including Sparta, Athens, Corinth and others, and the Persian Empire of Xerxes I.

The Persian invasion was a delayed response to the defeat of the first Persian invasion of Greece, which had been ended by the Athenian victory at the Battle of Marathon. King Xerxes had amassed a huge army and navy, and set out to conquer all of Greece. The Athenian general Themistocles proposed that the Allied Greeks block the advance of the Persian army at the pass of Thermopylae and simultaneously block the Persian navy at the Straits of Artemisium. An Allied naval force of 271 triremes was thus dispatched to await the arrival of the Persians.

Mardonius (Old Persian: 𐎶𐎼𐎯𐎢𐎴𐎡𐎹 Mr̥duniyaʰ; Ancient Greek: Μαρδόνιος Mardónios; died 479 BC) was a Persian military commander during the Greco-Persian Wars. Though he secured initial victories in the first Persian invasion of Greece, he was ultimately forced to retreat into Anatolia after suffering catastrophic losses in both men and material due to a storm off the coast of Mount Athos, following which he was relieved of his command by Darius the Great. He was later re-appointed by Xerxes I and took part in the second Persian invasion of Greece. In 480 and 479 BC, Mardonius spearheaded the Persian army's destruction of Athens. Shortly thereafter, he was killed during the Battle of Plataea.

Themistocles (/θəˈmɪstəkliːz/; Ancient Greek: Θεμιστοκλῆς; c. 524 – c. 459 BC) was an Athenian politician and general. He was one of a new breed of non-aristocratic politicians who rose to prominence in the early years of the Athenian democracy. As a politician, Themistocles was a populist, having the support of lower-class Athenians, and generally being at odds with the Athenian nobility. Elected archon in 493 BC, he convinced the polis to increase the naval power of Athens, a recurring theme in his political career. During the first Persian invasion of Greece, he fought at the Battle of Marathon (490 BC), and may have been one of the ten Athenian strategoi (generals) in that battle.

In the years after Marathon, and in the run-up to the second Persian invasion of 480–479 BC, Themistocles became the most prominent politician in Athens. He continued to advocate for a strong Athenian navy, and in 483 BC he persuaded the Athenians to build a fleet of 200 triremes; these proved crucial in the forthcoming conflict with Persia. During the second invasion, he commanded the Athenian navy at the battles of Artemisium and Salamis in 480 BC. Due to his subterfuge, the Allies successfully lured the Persian fleet into the Straits of Salamis, and the decisive Greek victory there was the turning point of the war. The invasion was conclusively repulsed the following year after the Persian defeat at the land battle of Plataea.