Leonidas I was the leader behind the Spartan military during the Greco-Persian Wars, particularly recognized for his role in the Battle of Thermopylae in 480 BCE. As king of Sparta, he commanded a small force, including his famous 300 Spartans, against a vastly larger Persian army led by Xerxes I. Leonidas’s leadership and strategic acumen allowed his troops to hold the narrow pass at Thermopylae for three days, delaying the Persian advance despite knowing they were outnumbered and facing certain defeat. His bravery and sacrifice have made Leonidas a symbol of courage and resilience in the face of overwhelming odds.