Battle of Marathon

The Battle of Marathon, fought in 490 BC, was the defining engagement of the first Persian invasion of Greece. A force drawn from the citizens of Athens, supported by a contingent from Plataea, confronted an expeditionary army of the Achaemenid Empire commanded by Datis and Artaphernes. Although the Persian force was numerically superior, the Greeks won a decisive victory that permanently altered the course of the Greco-Persian Wars and ultimately contributed to the rise of Classical Greek civilisation.

Background to the First Persian Invasion

The roots of the conflict lay in the Ionian Revolt (499–494 BC), the opening phase of the wider Greco-Persian confrontation. Persian rule in Asia Minor had generated discontent among its subject populations, and revolts broke out after a failed joint Persian–Milesian attempt to seize Naxos. Aristagoras’ abdication in Miletus sparked a wave of insurrections across Ionia, with cities expelling Persian-appointed tyrants and declaring themselves democratic. Seeking military aid, Aristagoras turned to the mainland Greek states. Only Athens and Eretria responded, sending forces that played a central role in the burning of Sardis, the satrapal capital. Although the rebels were ultimately defeated at Lade and the Ionian Revolt collapsed, the Persian king Darius I resolved to punish the offending mainland states.
Darius viewed Athenian involvement as a direct threat to imperial stability. Herodotus recounts that he dramatically vowed personal vengeance upon Athens, shooting an arrow toward the sky and instructing a servant to remind him daily: “Master, remember the Athenians.” This vow combined with Persian expansionism and concerns over further Greek interference prompted preparations for a punitive campaign across the Aegean.
Political developments within Athens had also contributed to rising tensions. The late-sixth-century reforms of Cleisthenes had introduced the conditions for democratic governance, and the Athenian citizen body became hostile to any outside interference, whether Spartan or Persian. The earlier appeal to Persia for support against Spartan machinations resulted in Artaphernes demanding “earth and water,” an expectation of submission. The Athenians’ sharp rejection of this demand and their role in the Ionian Revolt ensured that conflict with Persia became inevitable.

The Persian Expedition and the Landing at Marathon

In 490 BC Darius launched the first full invasion of mainland Greece. A naval task force under Datis and Artaphernes crossed the Aegean, subjugating the Cyclades and advancing towards Euboea. Eretria fell after a short siege, was sacked and its inhabitants deported. The Persians then crossed to Attica, landing in the wide Marathon plain, which offered space for deploying infantry but also restricted the positions from which heavy cavalry could operate.
The Athenians, joined by Plataean allies, marched rapidly to Marathon and occupied blocking positions at the exits of the plain. A runner was dispatched to Sparta for assistance, but the Spartans declined immediate support due to a religious festival. Thus the defence of Attica fell primarily upon the Athenian citizen army.

Deployment and Strategy

The Athenians selected terrain that hampered the use of Persian cavalry, a significant element of the Achaemenid force. Command was held by Miltiades, a general who had previously lived under Persian rule and understood Persian tactics. He resolved to seize the initiative and proposed a direct attack.
The Greek phalanx was strengthened on the wings and deliberately thinned in the centre. Miltiades aimed to lure the Persian elite troops into driving back the central Greek line, while the reinforced wings, advancing more effectively, would sweep inwards in an enveloping manoeuvre. This approach took advantage of hoplite equipment, cohesion and training.

The Battle

When the Athenians advanced at a run—the famous charge across the last stretch of ground—Persian missile troops unleashed volleys of arrows, but the heavily armoured hoplites closed the distance rapidly. The weakened Greek centre fell back under Persian pressure, but the stronger wings achieved their intended breakthrough. As they wheeled inward, the Persians found themselves enveloped.
The resulting collapse of the Persian line led to a rout towards the ships drawn up on the shore. Many Persians died in the marshes or were overwhelmed during the retreat. Those who escaped fled back across the Aegean, abandoning any immediate prospect of subjugating Attica.

Consequences and Wider Significance

The defeat at Marathon forced the Persians to withdraw and marked the end of Darius’s first invasion. Attempts to assemble a larger army were disrupted by a major revolt in Egypt in 486 BC, and Darius’s death soon afterward delayed further plans. Preparations eventually resumed under his successor Xerxes I, setting the stage for the massive second Persian invasion in 480 BC.
Marathon became a foundational moment in Greek historical memory. It demonstrated that the Achaemenid Empire—vast, wealthy and militarily formidable—could be defeated by a relatively small citizen army. It also proved that Athens, traditionally secondary to Sparta in military prestige, could prevail independently. The victory strengthened Athenian confidence, political stability and cultural ambition.