Name: Battle of Thermopylae
Date: 480 BC
Location: Thermopylae Pass, Greece
Leaders: King Leonidas I (Sparta), Xerxes I (Persian Empire)
Sides: Greek city-states vs. Achaemenid Persian Empire
Forces: ~7,000 Greeks vs. ~100,000–300,000 Persians (estimates vary)
Famous for: A heroic last stand. King Leonidas and 300 Spartans (alongside other Greek allies) held off a vastly larger Persian army for three days, becoming a symbol of courage, sacrifice, and resistance against overwhelming odds.