Final answer:
The Spartans utilized the phalanx tactic at the Battle of Thermopylae to create a wall of shields and hold off the Persian army. This effective formation allowed a smaller force to delay a much larger enemy, inspiring subsequent Greek victories.
Step-by-step explanation:
At the Battle of Thermopylae, the Spartans used a battle tactic called the phalanx, which involves creating a wall of shields to defend against the enemy. This tactic was part of the military innovations brought by the hoplites, citizen-soldiers who were motivated by civic virtue and paid for themselves, rather than a state-funded standing army. The phalanx was a formidable formation that allowed Greek soldiers to effectively hold off the larger Persian forces led by Xerxes in 480 BCE. Despite being outnumbered, the Spartans and their allies successfully delayed the Persian army at Thermopylae, which was a narrow pass where the larger Persian forces could not fully deploy their might. The Spartan king Leonidas led his troops in a heroic stand, wherein they fought to the death and inspired the Greek city-states to continue the fight, which eventually led to the defeat of the Persian navy at the Battle of Salamis. The Spartans' sacrifice at Thermopylae became a symbol of courage and determination against overwhelming odds.