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an ancient battle as a scientific near-extinction event

Bottleneck at Thermopylae Pass

Once every thousand years or so an event may occur of such magnitude, which stands out from all the rest so greatly, that it defines the epoch. Sometimes the events are natural, such as extinction events. Sometimes they are man-made, such as the Hiroshima bomb, or, perhaps, construction of the pyramids.

It is thought that the monster Toba supervolcano event in Indonesia may have nearly caused the extinction of the human species, some 70,000 years ago, in what is known as a "population bottleneck" or "genetic bottleneck": a catastrophic reduction in the population of a species itself becomes a critical event, defining the point below which the species cannot recover. At that point, the surviving gene pool that passes through the bottleneck window is greatly reduced from its previous diversity.

The ancient Persian god-king Xerxes attempted his invasion of Greece in the famous battle of Thermopylae in 480BC. At that time, there were only two prominent city-states in the known world which were "free": beholden to no one, and unwilling to submit to subjugation. Those were Athens and Sparta.

The question today is: had Xerxes succeeded, what would have happened to those seeds of freedom and democracy? This is a short chronicle of a different kind of near-extinction event: how the first tenuous flickering flame of liberty was almost snuffed out, at a narrow pass in ancient Greece called Thermopylae.

Oinochoe-Black Figure pottery era c. 520-510BC

Figure 1. Oinochoe-Black Figure pottery era c. 520-510BC. Click image for source page.

The Classic Thermopylae Story

This story has been told by many before, and more ably. My "sound-bite" version is below.

The year is 480 BC. Xerxes the god-king of Persia has led his hordes, a supporting cast of millions of men and animals, against the poor but free Greeks. Leonidas, king of Spartans, holds off the combined might of the Persian world with his select "300" warriors by making a stand at the narrow mountain pass at Thermopylae. Despite massively overwhelming numbers, Xerxes' troops are funneled or "bottle-necked" into this pass. They can only fight The Leonidas "300" hand-to-hand, a few at a time. Xerxes fumes that his own men are "slaughtered like sheep".

A local herder betrays the existence of a goat-path by which Xerxes' forces are able to surround Leonidas through a "back door" to the pass. At the end of six days, Leonidas has been killed, and his 300 are wiped out to the last man. But the Greeks back home are inspired to an eventual successful routing of the Persians at the Battle of Plataea. A defeated Xerxes is sent skulking home to Persia, with the remainder of his depleted forces following shortly.

The Wikipedia accounting of the Thermopylae battle states: "Both ancient and modern writers have used the Battle of Thermopylae as an example of the power of a patriotic army of freemen defending native soil."

There were at least two motion pictures exploiting this theme, notably in 1962 and 2007. Regarding the 1962 "The 300 Spartans" Wikipedia says:

The picture was noted for its Cold War overtones, referring to the independent Greek states as "the only stronghold of freedom remaining in the then known world", holding out against the Persian "slave empire".

Modern patriots who prize liberty and freedom will rightly point out that we have our own commemorations of liberty today. The United States has its signing of the Declaration of Independence and eventual victory in the Revolutionary War. Great Britain has its Magna Charta and other great historical pivotal points. France rightly prizes its French Revolution, also against tyranny.

As great and glorious as these defining moments were, it is fair (though mean-spirited) to argue that something like those was going to happen anyway. Even if the Americans had lost the war against King George, remaining a subject colony for a time, the new idea of freedom, the notion that human lives were not the personal property of kings after all, was causing vast social upheavals all over Europe. Those ideas came from somewhere. Where?

As to the question of whether there ever would be a Europe, and whether nations and individuals alike would ever have the right to declare tyrant-free zones: this all started, and almost ended, at the battle of Thermopylae in 480 BC.

This wasn’t Star Wars – it was the stuff Star Wars is made of. In fact, it is thought that George Lucas looked to Homeric ancient Greece for some of his cinematic inspiration.

The Ancient World

The ancient Greece of that time was a collection of dozens, hundreds of bickering, warring city-states. Along the shores of western Asia Minor (modern Turkey), on the east shore of the Aegean Sea, were all the Ionian and Doric cities of Homeric legend, including Troy. To the north of this sea were the Thessalians, smack in the way of any land invasion route from the east. On the western Aegean shores, on the peninsula called Attica, lived the Athenians; to their north dwelt their rivals the Thebes. On the mountainous Peloponnesian Peninsula to the southwest lived the legendary Spartans, who trained from birth to fight and destroy.

Region of Athens,. Sparta, Marathon and Themopylae

Figure 2. Athens and Sparta. From Herodotus' Histories, Strassler translation. Major sites of discussion are highlighted (Thermopylae, Marathon, Athens, Sparta). The entire land mass of Greece is in size roughly 200 miles east-west and 300 miles north-south. It is a large peninsular mainland consisting of two major land masses (Hellas, home of Athens, and Peloponnese, home of Sparta) connected by a sizeable land bridge. The coastline is irregular and includes hundreds of habitable islands. Surrounded by the Ionian Sea to the west, Mediterranean to the South and Aegean Sea to the east, this region is ideally suited to fostering maritime travel, exploration and trade.

The area above is roughly comparable to Northern California in size. So, the earlier Peloponnesian Wars (Athens/Sparta) would be comparable to San Jose laying siege to Sacramento. See full size image of Ancient Persia in the time of Cyrus [] to get an idea of the small scale that the contested area of Greece in southern Europe really represented.

For a scanned larger view of the two-page Strassler map plate, please click image above. Here you will see the circumference of the Aegean, around which Xerxes moved his armed forces. Starting with a staging area in Sardis, he worked his way around the coasts counter-clockwise, bridging the Hellespont just north of the legendary city of Troy, finally anchoring his fleet at Artemision, and sending his army inland to Thermopylae. As noted elsewhere, maritime skills and ships of that era did not allow fleets safe point-to-point navigation across the Aegean, so Xerxes' navy essentially tracked the ground forces off the coast, as the army marched around this sea.

Footnote 3 relates how the Persians regarded themselves as descendents of Perseus, of Greek mythology, from the city of Argos on this map.

As to Cyrus The Great, son of Cambyses, ruler of the mighty and growing empire of Persia, father of Cambyses II conqueror of Egypt, there is little record that he paid these Greek city-states much mind. However, the ancient historian Herodotus recorded that Croesus, king of Lydia (Asia Minor), "wondered if he would be able to check the Persian power before it became too strong." [1]

It is this same Cyrus II who was said to be the king who won freedom for all Persians. But by this "freedom" was meant freedom of one state from the interference and governance of another. This "freedom" had nothing to do with the personal liberty of individual citizens. Cyrus wrested control of Persia from the earlier Medes, then from the Lydian empire. It was his son Cambyses II who conquered Egypt, and it was Darius I ("the Great") who succeeded Cambyses II.

The First Superpower

Under Darius's reign, his region (modern Iran) became the world's first superpower. His rule was also marked by upheaval. The Ionians rebelled at the instigation of their troublesome neighbors in the Mediterranean, the Greeks. Darius decided to punish the Greek city-states with an invasion of overwhelming force, but his invasion failed at the Battle of Marathon. That battle was won by the Athenians with assistance from Platean allies, a combined force of less than half that of Darius's Persian forces, and with absolutely no assistance from Sparta, who promised they would try to drop by after their own religious festivals were over.

This is the nettlesome, divided and fractious Greece that annoyed and irritated the combined might of the Persian empire.

Unfortunately for Darius, his plans to re-invade and punish Greece with an even larger force were thwarted, as the Egyptians now revolted, and Darius himself died before setting foot in the newly re-subjugated Egypt.

It was left to Darius' son Xerxes to decide what to do about the Greeks once the problem with the Egyptians was settled.


This Xerxes the Great was young, ambitious and rash, possessed of a great desire to do something to establish himself as a worthy successor to Cyrus and Darius. Xerxes was also vain, and possessed of an unpredictable cruelty, which presumably he deemed appropriate for the most powerful man in the world.

At first, Xerxes did not even want to invade Hellas, but he was enticed to do so after numerous invitations to do so, and promises of support [2], from Greek enemies of Athens, such as the Thessalians.

We need to understand that the Ionian and Doric regions of Asia Minor, and the northern areas such as Thessaly, had in previous invasions and skirmishes received utterly no support from Athens, and had absolutely no reason to suppose support might be forthcoming against the Persians [3] (whom they called "Medes"). Similarly, the Ionian and Doric "buffer zones" on the mainland had no way of resisting the expansion of the Persian empire, and so these Greek-speaking regions, by a process known as "medizing", would pay homage to the rising star in Persia and allow themselves to become peacefully subjugated.

In other words, Xerxes was in part persuaded to go against Athens because of bad blood resulting from the incredibly poor relations of Athens with her neighbors.

With the counsel and planning of a Persian called Mardonios, Darius' first cousin, Xerxes planned a three year war against Greece, drafting the best young Persian warriors and a huge land and sea invasion force assembled from all of the various subjugated nations.

In this way Xerxes expected to punish Greece for their "insults" against Darius (namely, the Persian loss at Marathon), and Mardonios expected to win for himself the governorship of all Hellas when the war was successfully over.

Herodotus makes it clear for the modern reader [4] that neither Xerxes nor Mardonios had any idea of the vastness of European geography, nor of the extent of its population with tribes and city-states. Moreover, the Persians did not consider Athens would be a particularly formidable or resolute opponent, fully expecting Athens to capitulate to bribes and to weasel on any commitments it may have made with neighboring states.

Worst of all, to this reader at least, even Herodotus fails to pick up on the full significance of the fact that the Athenian and Spartan states, at this point in history, remained free and beholden to no one. Perhaps this is because the great historian could have no clue how this concept was eventually to shape the development of the western world.

Herodotus does report Xerxes' astonishment that the Greeks actually cling to this silly idea of freedom, and we see Xerxes wondering how much of a bribe it is really going to take for his assembled armies to not actually have to go to battle after all. We will see this underestimation again and again.

Flickering Flame of Freedom

Modern readers need to understand that freedom, as we understand it today, existed nowhere in the ancient world. This was not yet the "Golden Age" of Greece nor the early democracy of Athens of 508 BC. Both Sparta and Athens were slaveholding states, and "full citizenship" was a privilege, not a right, reserved for a very small ruling elite. By the fifth century BC, fewer than 1,000 in Sparta may actually have been full citizens. Most of the standing armies consisted of Helots, a subjugated people of the Laconia (Sparta) region who were used as domestic slaves and soldiers and who, inexplicably, accepted this role for centuries while serving as formidable surrogate soldiers for the tiny Spartan full-citizen population.

As for freedom in Persia, all bowed to the absolute life or death power belonging to the King alone. When Xerxes asked Pythios, a medized Greek, if there was anything at all he could to for this man, the man replied by asking if his oldest son might be withdrawn from military service to look after his father in his old age. Enraged, Xerxes ordered that the eldest son be found, cut in half, and the two symmetrical halves be placed on either side of the battle road, so that his armies could march between the two pieces, which is what happened. Thus did Xerxes withdraw Pythios' son from military service, fulfilling his pledge of gratitude to the old man. [5]

Our modern reaction to ancient Greek affairs of state might be that, well, perhaps they ought to have patched up their internal differences and sued for peace with Persia. After all, medized city-states were not exploited that badly, Persia recognized what a bounty of wealth grew in the fertile green valleys of Europe, and a healthy Europe ought to be worth more to Persia, by trade alone, than as a poor neighbor by any means. According to this thinking, with a properly negotiated and executed treaty, Europe might have inaugurated trade with Persia so lucrative that Xerxes could not have afforded to go to war.

I fell for this notion myself, at first. From the very beginning of recorded history, there had been nothing but fighting; there had been too much war. Then I saw that Xerxes, like so many absolute despots, was fully as insane as North Korea's Kim Jong-il, while also holding more military power than any nation on Earth.

Herodotus also reports that the modest all-Persian forces commanded directly by Xerxes and Mardonios were well-trained, loyal and very able, whereas other aides reported to Xerxes (at great risk to their own life for this honesty) that all of the other forces were from subjugated nations, who were only fighting because they were forced to, and who would be "utterly worthless" when the chips were down.

"Some Clown Named Eisenhower"

Another fact that becomes clear is that, while Xerxes and his vast staff were underestimating the military resolve and power of the Athenians, these Persians, having no previous combat experience with the Spartans (themselves absent from Marathon), had utterly no idea what this city-state of Sparta was all about. It is as if, 2,500 years later, Hitler understood the Allied resistance to consist of the very able General Montgomery "and some clowns named Eisenhower and Patton."

What Sparta and Athens did have, that the Persians, having none of it themselves, could not understand, was freedom. Almost alone of the combatant nations, Athens and Sparta had never paid homage to any other nation, and would prefer death to subjugating themselves to Persia.

Xerxes was setting himself up to step blindly into a hornet's nest. Neither did he have, nor could he have, any idea what in the world he was really dealing with.

Having considered all these factors to the best of his ability and patience, for the coming invasion of Greece Xerxes assembled the largest armed force with world had ever seen. According to Herodotus [6]:

517,000 Naval forces from Asia
1,700,000 Infantry
80,000 Cavalry (Persian)
20,000 Arabians and Libyans on chariot

Herodotus arrives at a total estimate of 2,641,610 in the fighting forces.

All told, including Phoenician and Egyptian engineers, supply masters, cargo ships, concubines, scouts, messengers and heralds and all others in support of the armed forces and its infrastructures, Herodotus further arrives at a total of 5,283,220 that Xerxes led to Thermopylae.

So, this juggernaut that Xerxes launched against infant Europe, whatever its true size, was much like our modern orbital rockets of the 20th and 21st centuries, which are 90% fuel, or, if you will, most of the fuel is expended at launch in the lifting of the fuel. And Xerxes has taken the better part of a year in moving this vast force anywhere near Greece, and how he actually did it is both somewhat remarkable, and humiliating.

By modern standards, the ancient triremes were hardly seaworthy, let alone ocean-going. They were perhaps 37 meters in length (121 feet). If caught by a storm in the inland seas of the region, the chance of losing the entire fleet was great. These navies puddle-jumped from port to port around the circumference of the great seas, like the Aegean, never point-to-point across the sea.

For this reason, and because the navy was totally inadequate to transport the armies and supporting forces, Xerxes directed the building of a pontoon bridge at the Hellespont (now called the Dardanelles). There had to be some way for his vast armies to cross over by land to all of the Grecian archipelagos, short of marching all the way around the Black Sea, and in this way Xerxes also felt he could impress the neighbors by making a statement of his power to command the taming of even the waters themselves.

The King's Temper Tantrum

Storms destroyed the first pontoon bridge, and Xerxes had the engineers beheaded. Even more pointedly [7], he had the waters of the Hellespont strait themselves lashed with whips, while his soldiers shouted insults at the water.

The invasion force worked its way over a rebuilt pontoon bridge, around the Aegean Sea through all of the lands of the subject states therein, depleting the towns of all foodstuffs, and literally drinking the rivers dry, if Herodotus is to be believed. The army staged in an area of Thessaly just north of a pass into the mountains which was the intended insertion point for a fighting force of over 2 million soldiers, both Persian and captive, into the Attica Peninsula.

There, Xerxes expected Athens to fall, and then Corinth, and Argos, and eventually, the entire Peloponnesian Peninsula and its irritating little tribe of people who called themselves Spartans.

"Xerxes listened but could not understand: that the Lacedaemonians [Spartans] were really preparing to kill or be killed, to fight as much as was in their power, seemed to him to be the height of folly, the action of fools." [8]

After a whole year of doing nothing except eating whole towns out of house and home, the mighty Xerxes caused the biggest invasion known in the history of mankind to be directed upon the spot the Spartans had chosen to resist Xerxes, and for what military objective?

Xerxes bottle-necked his entire vast armed force, at this pass called Thermopylae, which was barely wide enough at its throat to allow passage of a single ox-cart.

This may have been the bottle-neck that saved the world ... or destroyed it.

Leonidas of Sparta

Leonidas, King of Spartans, sent the Athenians and many of the Spartans home. He and the famous "300 Spartans" remained to defend the pass. Contemporary observers and historians alike believe Leonidas knew full well that the defenders remaining to face off the Persian hordes in the narrow pass of Thermopylae, whoever they might be, would die. Leonidas' goal was to hold the Persians off for six days until the remaining forces could get home and prepare defenses.

In one of the most famous battles of all history, this small force did in fact buy the Greeks the time they needed, but at supreme cost: Leonidas and his 300 Spartans were finally surrounded and slaughtered.

It was also at the famous battle of Thermopylae that the Spartan Dienekes uttered his memorable quotation. He was informed that whenever the barbarians shot their arrows, the sun was darkened by their number. He replied that this was good news, since he would prefer to fight the Medes in the shade. [9]

The rest of the Spartans and Athenians were able to use the six days to cooperatively mount a counterattack on Xerxes, with deadly effect.

The Greek naval forces were so superior that Xerxes retreated back to the Hellespont and home, fearing he would be cut off from the Persian mainland if his pontoon bridges were destroyed by the Greeks (who deliberately left them undestroyed to assist Xerxes in his flight from the region). Mardonios was left behind to complete the conquest of Greece, but Mardonios' forces failed, Mardonios himself was killed, and the remaining Persians were also driven home.

The Legacy of Thermopylae

It does not take a great stretch of historical imagination to suppose what might have happened if the brave Leonidas had been unable to stave off the advance of the Persians. Attica (which had actually been abandoned by the Athenians for strategic reasons) might have fallen for all time, and then the Peloponnese would fall, giving rise to the subjugation of the entirely of Europe as it was then known.

Even so, no empire lasts forever, and something else European would eventually have arisen, as it finally did to crush the crumbling Rome, but this much would have been lost:

The tiny, flickering flames of freedom, represented by those city-states of Athens and Sparta, so different in their constitution yet so alike in their resolve to remain free, might have been extinguished forever.

After the death of Mardonios, Herodotus [10] relates how the Spartan General Pausanias inspected the quarters of the late Mardonios, and, struck by the splendor of the gold and silver drinking cups and utensils, orders the Persian bakers and chefs to prepare for him a meal of the same sort they would have prepared for Mardonios. As a kind of joke, he also directs his own servants to prepare a simple Spartan meal as well.

When Pausanias had the chance to compare the two meals directly, he laughed and sent for the generals of the Hellenes:

"Men of Hellas, I have brought you here together, because I want to show you what an idiot the leader of the Medes was. This was his lifestyle, but he came to us, who have this miserable way of life, in order to deprive us of it."

The flame of freedom had indeed flickered, but it then survived to flourish in the Golden Age of Greece, giving us the very name democracy. It endured Alexander of Macedonia's conquest of the known world, including of Persia, though it seemed to have been extinguished in the cruel thousand years of darkness following the implosion of the republic of Rome.

Ironically, during that thousand-year slumber, knowledge of the history of the ancients and the Greek demokratía was preserved not only in the monasteries of medieval Europe, but in the records of Persia. While Europe slept its thousand-year sleep of the damned within plague-infested cities in constant warfare, the Islamic Golden Age kept recorded knowledge of the flickering torch alive, without sampling any of those freedoms for itself.

Xerxes had very nearly snuffed out the most precious gift the western world could ever offer humanity. Did Xerxes know that? Not understanding what is it to possess freedom, the mightiest King of the world's first superpower could never know exactly what it was that he lacked, which those "miserable" Greeks had.

The Insolence of Freedom

Xerxes as a political leader undoubtedly still sensed that the insolence of freedom is always a threat to tyranny, because even when it is the sincerest intent of the free to live in peace with the subjugated, those who see freedom, but lack it for themselves, always desire to possess it.

Without Leonidas at Thermopylae, it is entirely possible there never would have been any flickering torch of freedom to pass down through the ages. Did Leonidas know that? Leonidas was probably consumed with the immediate necessity of protecting the homeland from invasion. But he obviously sensed and embraced the positive case, for which Xerxes would have sensed and feared the negative: without freedom, there is nothing worth fighting for.

It might just be that we owe Leonidas an even greater debt than we already give him credit for.


Figure 3. Leonidas. Image from Wikipedia Common. Hero of the Battle of Thermopylae, King Leonidas with 300 fellow Spartans held off a Persian invasion of 80,000-290,000 soldiers of Xerxes' army. According to Wikipedia, the Greeks killed roughly 20,000 of the Persian troops while losing 2,500 of their own in this narrow pass. Leonidas sent most Greeks back to the homeland to prepare for its defense. Unfortunately Leonidas and his remaining 300 personal bodyguards were slain while holding off the Persians. Xerxes truly never understood why these men would prepare to die in defense of their homeland. It is said the Spartan feat of valiance rallied the Greeks to their then-successful defense of the Grecian peninsulas, in a stunning naval victory, driving Xerxes' generals back to Persia to look for easier pickings.


copyright ©Alex Forbes August 25, 2009


All references to Histories, Herodotus and editor Strassler are interchangeable. An irritating anomaly of the citation notation, if you are looking one up, is that the sort order is cardinal, not decimal as we might expect: 7.189 is the 189th citation in Book 7, not the citation that you might logically look for between 7.1 and 7.2.

The Landmark Herodotus - The Histories is available from major booksellers, including Barnes & Noble and Amazon. The Robert B. Strassler edition is said to be best for its organization, references, indexing and footnoting, with very competent translation, while other translations may offer more dramatic translation at the expense of some of the trappings of a really good reference work.

Thanks to Dave Norton for his encouragement and suggestions in the editing of numerous drafts of this document.

1 Herodotus, Histories, Strassler translation, 1.46. In fact, Croesus' Lydia was the first to fall, to Cyrus, and Lydia'a ancient capital of Sardis became the staging area for Xerxes' advance across the Hellespont to the regions of Thrace, Chalcidice, Macedon and Hellas.

2 Herodotus 7.5, 7.7. At first, with the rebellion of the Egyptians on his plate, Xerxes had no desire to march on Hellas.

3 It's of some historical interest that the Persians considered themselves descendents of the legendary Greek Perseus, and Xerxes claimed bondage to the ancient Argives, or people of Argos [Figure 2]. For this reason Xerxes appealed to the Argives to stay out of the impending conflict, implying that they would be treated well. [Herodotus 7.150]

4 Herodotus 7.50-7.51: Strassler remarks upon Xerxes's "appalling ignorance of the geography of Europe."

5 Histories 7.38. Pythios asks Xerxes to release his eldest son.

6 Herodotus 7.189. These numbers are Herodotus's estimates, and not some official Persian census of the war effort, so the numbers appear to be more exact than they really can be. Further, modern scholars assert (Strassler Appendix R) that these figures, though suggesting the appearance of being precisely calculated, are greatly exaggerated: an army 5 million strong would have to march in a column 2,000 miles long, so that as the head of the column arrived at Thermopylae, the tail of the column would just be leaving Susa, in Iran.

7 Herodotus, 7.35. Evidently this kingly temper tantrum made quite an impression on the world of his time - as it should have. In a modern war crimes trial, this would have been used as evidence of criminal insanity.

8 Histories 7.209. Xerxes asks Demartos what the Spartans are about.

9 Histories 7.226. Dienekes prefers to fight in the shade.

10 Histories, 9.82. Pausanias' comparison of the Persian meal with the Spartan meal.




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