In the Persian War the Opuntian Locrians fought with Leonidas at the Battle of Thermopylae, and also sent seven ships to the Greek fleet. The Locrians fought on the side of Sparta in the Peloponnesian War.
During the Persian Wars, the Opuntian Locrians joined Leonidas' forces at the Battle of Thermopylae and contributed seven ships to the Greek navy.  They sided with Sparta during the Peloponnesian War.