At which battle did Athenian forces defeat the Persian army during Darius I’s first invasion of Greece?

Athenian forces defeated the Persian army at the Battle of Marathon during Darius I’s first invasion of Greece.

The battle took place in 490 BCE on the plain of Marathon, northeast of Athens. Darius’s expedition sought to punish Athens and Eretria for supporting the Ionian Revolt and to strengthen Persian influence in the Aegean. The Athenians, supported by Plataea, attacked the Persian landing force and won a significant victory.

Herodotus is the principal surviving narrative source, though the exact size of both armies remains debated. The Athenians later commemorated the dead with a burial mound at the battlefield. The famous story of a runner carrying news to Athens belongs to later tradition and should not be confused with the full military history.

Marathon did not end Persian interest in Greece. Darius’s son Xerxes launched a much larger invasion ten years later, leading to the battles of Thermopylae, Salamis, and Plataea.