Every year, Golden Dawn, an anti-immigrant Greek neo-Nazi party, holds a rally at a rugged mountain pass once known as the “hot gates," because of the sulfuric springs bubbling beneath. It's the site where a small band of Spartan warriors stalled the might of the advancing Persian empire almost 2,500 years ago. The Golden Dawn members gather, torches in hand, around a bronze statue of the Spartan King Leonidas — who famously perished alongside his 300 companions — sing the national anthem and chant far-right slogans. “Greece belongs to the Greeks!" goes one cry. “People! Army! Nationalism!" is another.

The ancient Battle of Thermopylae, though, doesn't resonate only with them. In a year defined by growing right-wing nationalism on both sides of the pond, it remains a curiously conspicuous rallying cry for myriad populists and conservative movements. And that includes American supporters of Republican presidential nominee Donald Trump.

Beginning with the account of Greek historian Herodotus, the clash, which took place in 480 B.C., has become a kind of foundation myth of Western civilization. The heroic Spartan stand -- whose numbers were closer to 7,000 than 300 -- in the face of the mongrel, polyglot Persian hordes is cast as a primordial act of sacrifice for the liberty of a people. The historical consensus, both among ancient chroniclers and current scholars, was that Thermopylae was a clear Greek defeat; the Persian invasion would be pushed back in later ground and naval battles. But its legacy still reverberates millennia later.

“The Spartan chant,'We are what you were; we will be what you are,' " 19th-century French philologist Ernst Renan wrote in his seminal treatise on the idea of a nation, “is, in its simplicity, the abridged hymn of every fatherland."

And consider the opening narration to the 1962 Hollywood film “The 300 Spartans" -- the cinematic precursor to the campy, overly-stylized 2007 "300." At a time when the Cold War was in full swing, it set down the stakes of a clash with the East:

Across the hush of 24 centuries,
this is the story of a turning point in history.
Of a blazing day
when 300 Greek warriors fought here,
to hold with their lives
their freedom ...
and ours.

This is a powerful claim that many in the West intuitively accept: Thermopylae is the Alamo of antiquity, a doomed contest between the brave few and a gargantuan foe that stirred their compatriots to action. Had Xerxes, a Persian emperor, snuffed out all Greek resistance, then the scattered city-states on the western side of the Aegean Sea would have just become one more province of what was a vast, mutli-ethnic empire.

What would happen to our supposed Greek inheritance — the principles of democracy and reason?

Frank Miller, an American graphic novelist whose work gave rise to the "300" film series, sketched the implications most crudely with his book: “The army of Persia—a force so vast it shakes the earth with its march — is poised to crush Greece, an island of reason and freedom in a sea of mysticism and tyranny."

Whatever the historical merits of this belief — and more on that below — the ghost of Leonidas looms large in the right-wing imagination. A host of far-right groups, including neo-Nazi organizations in the United States and Australia, have invoked this history in their own political iconography. The anonymous blogger who translated the anti-immigrant writings of Norwegian terrorist Anders Breivik into more than a dozen languages went by the screen name “Angus Thermopylae."

You can get a taste of the phenomenon through a search on Twitter or Google for the phrase “Molon Labe": translated roughly as “come and take it," the laconic response Leonidas is said to have given to an envoy of the Persian emperor who demanded the Spartans lay down their arms.

Since the popularization of the "300" story, “Molon Labe" became a kind of code word for gun-rights supporters in the United States, as well as the tea party movement, a catchall slogan for those irked by the invasive power of the federal government and the supposed leftist aim to take away their weapons. On social media, that messaging now co-exists with #maga — “Make America Great Again" -- and other online slang used by Trump supporters.

One example: Molon Labe Industries, an online store for right-wing paraphernalia that has more than 300,000 subscribers or “likes" on its Facebook page, melds a whole range of right-wing memes, as can be seen in this image of its Facebook page:

The echo of Thermopylae and the lionization of the Spartans is popular among the fringe American ultranationalists and online xenophobes who have come to be known as the “alt-right."

Earlier this year, a YouTube user named “Aryan Wisdom" uploaded a video where scenes from "300" were edited over with speeches from Trump and his political rivals. The Republican nominee, unsurprisingly, is cast here as a Spartan warlord, facing down a callow President Obama and the man behind it all — Xerxes, or in this case, the American financier George Soros.

The video makes the Persians out to be bomb-throwing Muslim terrorists, Obama a feckless lieutenant to dark forces, and Hillary Clinton a slave to the lusts of a “globalist" -- hint: Jewish — elite. It has been watched more than 2 million times.

And myriad Trump supporters invoke Thermopylae in their celebration of the Republican candidate:

Golden Dawn, which overtly clings to the mythic legacy of the Spartans, is now the third biggest political party in Greece, despite a record of racially-instigated violence and Nazi apologia. Last month, it formally endorsed Trump from the floor of the Greek parliament, hailing the “patriotic wind" blowing through Europe and across the Atlantic.

“It’s blowing in the United States, where it appears that the next president will be a patriot president," said party spokesman Ilias Kasidiaris. He went on: “The geopolitical balance will change. And most interesting of all is that tomorrow’s president of the United States is supported in Greece only by Golden Dawn."

Trump himself may not appreciate having such admirers from afar. But the politics channeled by his campaign are part of a larger far-right populist turn in the West, as WorldViews has documented over the course of the year.

Moreover, the symbolism of Thermopylae is disconcertingly relevant to the ideology of the European far right.

“Ancient Sparta is proto-fascist," Paul Cartledge, a celebrated British classicist and author of “Thermopylae: The Battle That Changed the World," among numerous other works on ancient Greece, said in an interview with WorldViews.

Although the clash between Greeks and Persians may be remembered now as the battle that crystallized Western liberty, the ancient Spartans were no model democrats — even in their time. Their society was communal and militarist. It practiced early forms of eugenics and infanticide. It kept a huge slave population in thrall to its warrior elite. Some contemporary scholars even liken conditions in the city-state to a kind of apartheid.

For all these reasons, Nazi leader Adolf Hitler happened to be a huge admirer of Sparta.

“Sparta must be regarded as the first völkisch state," Hitler once said, referring to a racially ordered polity. “The exposure of the sick, weak, deformed children, in short, their destruction, was more decent and in truth a thousand times more human than the wretched insanity of our day which preserves the most pathological subject."

In his desolation of Europe and mass slaughter of millions, the Nazi leader saw himself marching in the wake of Spartan hoplites.

And what about the Persians? As much as they've come to symbolize an alien menace, an Eastern Other, an empire floating in a “sea of mysticism," they weren't all that different from the Greeks they were fighting.

Greek-speaking troops from the western ends of the Persian empire formed a crucial part of Xerxes's army. There's evidence, too, that Greek-speaking cities ruled by the Persians were afforded their own system of democracy. Tyranny, a Greek word, was a practiced form of government in various Greek city-states. Persian-ruled cities like Babylon and Taxila, in what's now Pakistan, were home to great centers of science and learning.

“It’s a clash of political civilizations, it’s not a clash of religions," Cartledge said, arguing the difference between the two sides was less cultural than it has been made out to be. “Xerxes didn’t conduct his campaign on the basis of a crusade."

And, ultimately, for all the heroism of the Persian wars, the Greeks would turn against one another. In the wake of the Persian retreat, the rival powers of Sparta and Athens built regional alliances and mini-empires of their own and soon locked horns in three decades of ruinous conflict that spanned the Mediterranean.

“The Greeks fought each other as much they fought others," Cartledge said.

At a time when nationalist movements are rallying around the mythic, patriotic deeds of the past, it's important to remember how fleeting those moments can be.

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