Forgotten Heroes of Thermopylae

James S. Robbins writes about those other defenders at Thermopylae:

The Spartans used the rallying cry of “Hellas for the Greeks” when it was convenient for them, but they were well known for only fighting when the interests of their city were at stake. Even Leonidas’s self sacrifice at Thermopylae was conditioned by an oracle’s vision that Sparta would either lose one of its kings or be destroyed. As well, Herodotus observes that Leonidas was motivated by “the wish to secure the whole glory for the Spartans.”

If you can’t quite get behind rooting for the Spartans, there were other heroes on the scene at Thermopylae, people the movie ignores. Herodotus tells us that when it became clear that the Greek defensive position had been flanked, Leonidas ordered the men from the other Greek states to leave, to prepare for the confrontation yet to come. But the 700 men of Thespiae, led by Demophilus, refused. They chose to stand with the three hundred Spartans, to fight beside them. “So they abode with the Spartans,” Herodotus wrote, “and died with them.”

Who were the Thespians? No, not actors — hard to imagine seven hundred or even seventeen taking up arms these days. They came from Boeotia, near Mt. Helicon, a little more than midway between Thermopylae and Athens. Their polis was traditionally a democracy. The Thespian Hoplites were much more akin to the volunteer citizen soldiers long seen as the backbone of the American fighting forces. Unlike the Spartans, the Thespians did not spend their lives drilling and training for war while living off the sweat and toil of those the enslaved Helots. The Thespians were free men who lived freely, and defended their city because their conscience demanded it.

I know that 300 concentrated on the Spartans, as did the graphic novel on which it's based. Read Steven Pressfield's Gates of Fire, especially near the climax, to get a real feel for the Thespian sacrifice.