A Greek army led by the Spartan Pausanias routs the Persian land army under Mardonius, ending Xerxes' invasion of Greece.
On that day the Spartans, as the oracle had foretold, gained from Mardonius their full measure of vengeance for the slaying of Leonidas, and the most glorious of victories of all which we know was won by Pausanias, the son of Cleombrotus, who was the son of Anaxandrides.
With the Persian navy's defeat at Mycale, reportedly on the same day, the battle decisively ended the invasion, and it is said to have laid the way for Athenian dominance in the Aegean and Alexander's later conquests.
Based on Wikipedia: Battle of Plataea
The destruction of this army, and the remnants of the Persian navy allegedly on the same day at the Battle of Mycale, decisively ended the invasion.
The battle is said to have laid the way for Athenian hegemony in the Aegean, the end of the Achaemenid power and the concurrent conquests of Alexander.