Plague - The Destroyer of Empires

[CNV2855]

You might have remembered me from earlier, when I made the case that Lorica Segmentata was not abandoned because of utilitarian reasons or inadequacy, but because of the staggering inadequacies when it came to finances and skill, as well as lost knowledge.

With so much new research being done, I am putting forth a pretty bold statement that is relevant to my previous train of thought regarding the disappearance of the earliest plate armor.  

Plague, more so than any other cause, has been the destroyer of empires from the beginning of time.  

Plague weakens the population, causes economic and social calamity, destroys the fabric of society, causes a resurgence of religion at the expense of secularism, and much time spend at other endeavors is spent lamenting the horrid reality, burying the dead, trying to fill stations with people who lack experience, massive drops in literacy, and harms pretty much every facet of any civilization.

Before I get to Rome, let me say that the Plague of Athens was a blow from which mighty Greece which only a few generations prior had nearly conquered the World.   Smallpox reduced the native population of the Americas by over 95%, so much so that had Smallpox been present, we would not have been able to subjugate the natives until the dawn of industrialization. 
The Mayans were devastated by plague (or heavy drought).  The Aztecs laid low.  Greece brought to ruin.  Mighty Parthia were easy pickings,  Various Chinese dynasties.  So many great powers have had disease discussed at length in their twilight.

...then we come to Rome.  Pax Romana.  From the reign of Octavian (although Rome was very much prosperous throughout the 1st-2nd centuries BC) to the reign of Marcus Aurelius.  
It was hit by Smallpox from Parthia, which was another Empire that faded away, weakened by disease.  

People love to think of the Crisis of the Third Century as the causative factor for the beginning of the fall.  It was merely correlation, a symptom of weakened Roman society.

Rome lost 100,000 trained soldiers to a storm in the First Punic War, was able to shrug it off and slug it out with Carthage and defeat them.  100,000 men.  They lost nearly half a million more during the 2nd, and still were victorious.  Wars do not killed families, babies continue to be born, the population either remains stable or rises.  Soldiers are easily replaced; it's when the family unit is slaughtered that the population is lost.

Let's look at the population estimate.  We know that Europe was at it's height during 200BC to 100AD.  Then:

The population levels of Europe during the Middle Ages can be roughly categorized:[1]

• 200–600 (Late Antiquity): population decline
  
  
• 600–1000 (Early Middle Ages): stable at a low level, with intermittent growth.
  
  
• 1000–1250 (High Middle Ages): population boom and expansion.
  
  
• 1250–1348 (Late Middle Ages): stable or intermittently rising at a high level, with fall in 1315–17.
  
  
• 1348–1420 (Late Middle Ages): steep decline.
  
  
• 1420–1470 (Late Middle Ages): stable or intermittently falling to a low level.
  
  
• 1470–onward: slow expansion gaining momentum in the early 16th century.
  

What caused the population decline starting near 200 AD?  The Antonine Plague.  Smallpox.  The single most deadly pathogen known to man.  Two emperor's, entire cities, and much of Rome was ill-fated due to this epidemic, which also caused the collapse of Parthia.  It continued with outbreak after outbreak, never really relenting.  Plague of Galen, Plague of Justinian, and so forth.  The population of Europe was in constant decline, and battles were fought with mere thousands when before the Empire could field armies in the hundreds of thousands.


I can't find the exact quote, but weren't there almost five times as many ship wrecks found for the 1st century AD than all of the 3rd/4th/5th showing a dramatic decline in commerce?  There were simply less people, less economic output, less GDP, and a much smaller army, with a lack of men of Italian birth.

It's during this time that Lorica Segmentata fades from use.  Not because the armor lacked merit, but like so many other things was one of the first signs that the Empire had been dealt a blow from which it would never recover, although it would take centuries to truly die. This isn't to say that there weren't other crisis' which weakened the Empire, but those were symptoms of a civilization suffering from ill health. Barbarian incursions, monetary debasement, reliance on mercenaries, massive conversion to Christianity. These did not cause the fall, but were symptoms of a sickened society trying it's best to stay afloat, and they did a splendid job managing to survive nearly centuries of chaos.

Without Smallpox, It's entirely possible that the Western Roman Empire may have never fallen as they had vast treatises on military warfare, were capable of some of the most magnificient war machines (ballista, and the early crossbow which would be re-invented 1,200 years later), plate armor and the advanced metallurgy involved, aqueducts, a standing army that served as engineers and maintained the public works, great planning, great thinkers, and repositories for great amounts of knowledge. Pax Romana was the height of civilization up until the modern age.

Even the citizens of the Middle Ages viewed their civilization as dwarfed by the sheer sophistication of the people who had come before.

[Second part of my argument is that this is why Segmentata was abandoned. It was used over 200 years during the Empire's height, a sign that it was effective. With the abandonment of Segmentata, the Pilum, and Scutum were also abandoned. Pilum were extremely expensive to make and extremely effective in trained hands. The replacement equipment was much cheaper, less effective, and we also see many Ballista during the 3-5th centuries become too expensive to maintain as part of defensive works.)

Look at the well made example of a Pilum in his hands. It's a work of art. It didn't bend, and it was a well balanced defensive and throwing spear. Plumbata were cheap alternatives.
https://www.youtube.com/watch?v=9EVrKWXHO9U
https://www.youtube.com/watch?v=65n3PpjPK04

It all boils down to economics, and if you ask an economist what happens if society were to lose 50% of it's population over the course of five years, I'm sure you'd be quite convinced by his answer. Centralized governments were unable to weather epidemics as well as the de-centralized Feudal system which rose to prominence again in Europe and Japan.

Edit: If one wants to look at historical literacy rates. Literacy was higher than 30% during the height of the Empire, but fell to lower than 3% during the 3rd century. Why? People who were able to read and write, and pass that knowledge on had died. Lots of them, and those who had survived were pre-occupied with continuing that tradition with the newer generations.

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Let's take another perspective. The Romans did suffer the loss at Teutoburg, which wasn't the fault of the legions, but of Varus. The Romans retaliated in a series of very successful campaigns of retribution which laid waste to Germanic society. Roman infantry was superior and had no problems dealing with contemporary Germans.

Fast forward to the 8th-10th century and barbarians from Scandinavia equipped very much the same as Germans, except with Longships, laid waste to most of continental Europe.

Had the 1st-2nd century Romans been around, the Vikings would have been a footnote in history. The infantry during the early Principate was the best heavy infantry up until the 14th century, and would've laid waste to most armies of the Middle Ages.

[Bryan]

You think this is extremely expensive to make? Why?

[CNV2855]

Rome, at it's height, during a period in which it had almost infinite funds chose to equip their soldiers in this fashion. They were sent into the field with the very best weapons, or what they thought of the best, at their day. When the Empire faltered, and money became debased, and the army began having problems...we see their ENTIRE kit changed. This wasn't for efficiency, as it coincides too perfectly with other internal problems. This was a financial decision. They had to cut corners, and could no longer afford the luxuries.

The Pilum is so effective it could penetrate a shield all the way up to it's wooden shaft, and possibly into the warrior holding that shield. That warrior wouldn't have time to pull it out, and he'd have to discard his shield, or have a very underwielding heavy stick hanging off of his shield, placing him at a terrible disadvantage. These weapons probably killed and maimed massive amounts of men. They're probably one of the most underrated battlefield weapons of all time, and there's just absolutely no chance that small Plumbata darts had the same effect.

As far as the pilum, you don't hand two of them to each legionnaire and call it a day. They need to throw these things a couple hundred times to become proficient. They would need to be replaced. They would require standardization and some standardization to ensure that a legionnaire would throw something familiar to him.

A sword in the Middle Ages could cost a fortune. These weren't soft iron, and they did not bend when impacting the shield. They were too expensive, and too hard to build for them to be a fire-and-forget weapon. They'd salvage the ones that they could after the battle and re-use them. They had so much metal so that the opponent could not chop them off at the hilt. Iron would protrude from his shield, and he'd be unable to remove it before lines would clash.

https://www.youtube.com/watch?v=9EVrKWXHO9U

Please watch this video in which he compares a cheap mass manufactured replica vs a handmade authentic pilum. It's clear that a lot of work went into constructing these, and that they were very, very efficient and dangerous weapons that could double as spears at a moment's notice. Everything from the tapered point, to the very thin tip, and the balance to achieve optimum results. After you watch that video, you can't come away thinking that plumbata were superior.

Not only that, but Ballista, and their handheld variants, started disappearing. Was the Ballista an ineffective weapon? It could hurl a bolt that could penetrate armor and pin a man to a tree at 1,500 yards. It's handheld copies came to dominant Europe and were so effective the Pope deemed them against Christendom. Cost, skill, and lost knowledge are the only reasons for those weapons to fall into disuse. The crossbow is one, if not the most, dominant weapon of the Middle Ages. Why was it abandoned by the Late Romans? Certainly not because of ineffectiveness. Europe reinvented the wheel; a weapon capable of penetrating the heaviest plate of its day.

The Scutum remains the best riot shield we use today. The oval shield, yes, has advantages on horseback...but also due to simplicity and cost. The Vikings used small round shields for their shield walls, even though their fighting style was similar to the Romans. I'm sure they'd have preferred the Scutum had they had the means, resources, and knowledge to produce them.

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I'd also like to add that I think desertion rates were exponentially higher in the Late Empire than during Pax Romana. Desertion was something plagued the US army up until the mid 20th century, and most armies through history. People sometimes felt like going on, and would leave. The Late Empire's mercenary armies were probably more prone to this, and a soldier walking off with his kit consisting of darts, a small shield, a spear, and a simple sword was probably less costly than if they were to walk off with the kit of an early Legionnaire.

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Please watch that video to understand how painstaking it was to construct a good pilum, and just how massively effective a pilum volley must have been. They seem to have had no problem piercing almost any obstacle of the day. Augustus loved his soldiers. He did not haphazardly equip them. I think we can assume that the Pax Romana legionnaire was the most effective fighting force up until gunpowder.

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We have evidence for crossbows up to around 146ad and then they disappear until the Battle of Hastings in 1066. I'm not an expert in this field by any means, but that's what I was able to dig up. Why was such an effective weapon discontinued for 900 years?

[Bryan]

That video doesn't show constructing pilum. Sim's Iron for the Eagles discusses it in detail, all told it was one of the easier iron products a castrum smith could make. I don't know where you're getting that it's difficult to make or even hard to use, it's a good design but it's just a javelin, not a miracle weapon. Plumbata were useful because they gave the legionnaires multiple missile weapons while also allowing them to use longer spears as their primary weapon, possibly to hold back cavalry.

[CNV2855]

I've provided my evidence that points to a drastic decline in all areas ca late 2nd century.  The Principate was clearly superior to the Late Empire and Tetrarchy, and it's far more convincing and likely than Gibbons assertion that Christianity drained the Romans of their martial spirit.  That superiority extended to the military, which had higher literacy rates, and a near unlimited pool of wealth to draw from.   Octavian had the world's most powerful military at his fingertips, from the dawn of human history until the age of gunpowder.

Constructing 20,000 disposal weapons to a certain standard every 3 months or so is definitely not an "easy" task.  They have to be balanced, and they're definitely more resource intensive than plumbata. 

It doesn't explain the disappearance of all of the other kit along with their plate armor.  Caesar himself says the Pilum is excellent in an anti-cavalry role, and the entire bit about the iron bending so they couldn't be pulled out is complete bollocks.  They were made of very thin iron so that they could penetrate, but they were solid and weren't prone to bending.

They did not always throw both of their Pilum, and if you can imagine 5-10,000 of these things flying into your ranks, especially with your first rank engaged, it must have been a terrifying ordeal.  These aren't arrows which would ricoceth, get caught in your mail and be a hindrance, hit the ground, cause minor wounds, or generally just bounce off your armor.  If you, or any part of your gear were hit with Pilum you were either dead or disabled.  

They would pierce mail and undergarments.  They would render shields almost entirely useless, as well as peircing the shield, the armor, and the man behind that shield.  They were the pinnacle of javelin technology because of their balance, reach, and that they could not be cut out.  

When equipment is standardized for four centuries in a society that could afford to equip its soldiers with the very best gear of Antiquity, the Pilum would've died out long before the reign of Marcus Aurelius.  

The Crisis of the Third Century is a turning point in so many things.  Literacy fell, trade was abandoned, capitals moved, demographics changed, the Empire became more Greek, financial burdens surfaced, and civil wars became the norm.  It's in this turmoil that every piece of gear that defined the legion was changed.  

In an alternate universe in which the Japanese were winning the Pacific War, and historians looked back and wondered why we started building massive amounts of PT boats, instead of carriers even though they had proven far superior... it'd be economical.  Massive amounts of small, short range, wooden vessels capable of doing relatively large amounts of damage for their size were an economical choice.  Plumbata, were easier to train with, cheaper to train with, cheaper to equip the legions with, but they weren't as effect as a 7lb javelin.

You guys think that because things were phased out, that what followed was superior.  Look at the grease gun and compare it to the Thompson submachine gun.  Simplicity, quantity, and economics play a role in warfare.   The Romans could not continue arming the legions as heavily as they had, and they transitioned from a very heavy infantry to a medium infantry interspersed with moderate amounts of cavalary, as well as the armies becoming much smaller.

As I said earlier, why did the Vikings who were almost exact replicas of the Germans the Romans faced in the 1st century have so much success against the Franks and Saxons, who had ravaged the Empire, if military technology did not lose it's effectiveness?

Civilization does collapse.  Knowledge can be lost.  It's a phenomenon that is well documented and does exist.  Civilization (along with the population) peaked in the 2nd century only to suffer a massive blow, the collapse a gigantic bubble, that spawned the widespread conversion of Christianity, and irrevocably changed Roman society.  You cannot tell me that in this period of strife, the army was as effective as ever!  Bullshit.  The Ursuper generals were struggling to pay, provide, and equip their soldiers.

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Also want to add that I do believe there's a small possibility that the Phoenicians knew of the Americas.  We'll never know since so much knowledge was lost.  We know roughly 2,500 years of our 150,000 year history.   In those 150,000 years, technology was invented, lost, and reinvented god knows how many times.  If a civilization had invented something and was annihilated, those ideas, those inventions would be lost only to be rediscovered.  

It's so easy to forget this, with the internet, with printing presses, with books, and all of our learning medium.  In a society in which you learned from a tutor and you were his sole student, and papyrus was extremely expensive, knowledge was in high demand.   When the economies that support the upkeep of knowledge are forced into disarray, then things are lost.  

I say all this because I think Lorica Segmentata is probably one of the most effective armor types for a thousand years.  It wasn't abandoned due to poor qualities.  They used that armor for two centuries with pride.  Two hundred years, at a time when every legionnaire could have been given mail if it was so preferred.  Plate offers a protection against weapons that surpasses that of maile, and full plate granted the wearer near full invulnerability on the battlefield.  Munitions grade Spanish plate could stop musket balls.

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[Timus]

It all boils down to economics, and if you ask an economist what happens if society were to lose 50% of it's population over the course of five years, I'm sure you'd be quite convinced by his answer. Centralized governments were unable to weather epidemics as well as the de-centralized Feudal system which rose to prominence again in Europe and Japan.

I'm an economist and I don't know the answer to that question. For all I know, your country just lost its less productive part of the workforce and now labor productivity growth is skyrocketing, generating surplus, investment, innovation, etc etc.
However, I also still have an ounce of common sense left, and I don't believe a group that lost 50% of its number will be able to maintain its cohesion easily. So yeah, you may be right right, just doesn't have much to do with economics.

[Nathan Ross]

With so much new research being done

Hi CNV. The points you're making here are the same ones you made in your thread Another Primary Consideration...

You don't seem to be bringing any new evidence or argument in here, just repeating what you said before. Could you point to some of the 'new research'?

Plague weakens the population, causes economic and social calamity, destroys the fabric of society, causes a resurgence of religion at the expense of secularism... and harms pretty much every facet of any civilization.

Not necessarily. As we discussed before, plagues can indirectly aid the development of civilisations. The Black Death did not end civilisation in medieval Europe - it led indirectly to the Renaissance. The plague of the 1660s did not end civilisation in England. The Native American societies were not destroyed by smallpox, but by the European colonists who brought the smallpox, and who prospered at their expense.

The Roman empire continued after the Antonine Plague, and reached its greatest extent under the Severans. Doubtless the plague, and recurring epidemics after it, changed Roman society, but it was not the sole cause of change.

What caused the population decline starting near 200 AD?  The Antonine Plague.  Smallpox.

We have very few ways of assessing population density and decline during this period, and the effects of the plague are hard to judge (no evidence for cities being entirely wiped out - estimated losses range from 1% to about 15%). But the Roman army seems to have reached its greatest size under Severus and continued to maintain very high numbers for a century or more after his time.

It's during this time that Lorica Segmentata fades from use.  Not because the armor lacked merit, but like so many other things was one of the first signs that the Empire had been dealt a blow from which it would never recover

As we discussed before, the lorica segmentata faded from use over the course of the 3rd century, and was apparently still in production throughout this period. Military equipment falls from use when it is no longer useful, or when the infrastructure needed to produce it fails - not when people forget how to make it.

When the Empire faltered, and money became debased, and the army began having problems... They had to cut corners, and could no longer afford the luxuries.

Again, discussed before. The late Roman state was richer than it had ever been, and the solidus provided a stable economic base throughout the 4th century. Late Roman arms and equipment were often of very high quality - metallurgy and sword production had improved since the 1st century, and the Roman state provided its field troops with gilded helmets. They were not cutting corners!

We have evidence for crossbows up to around 146ad... Why was such an effective weapon discontinued for 900 years?

We have a small amount of evidence for the crossbow as a hunting weapon in Gaul at some point in the 1st-3rd century. We have no evidence that it was ever used by the army. If it was, the various units of ballistarii in the late Roman army are a far likelier candidate than anything known in the Principiate.

[Edit - there have been suggestions that the Byzantine cheriotoxobolistrai were hand-held crossbows (cf John Haldon, Theory and Practice in Tenth century Military Administration). If so, then their use must have died out before the time of Anna Komnene, who claimed that the crossbow of the 'Latins' was unknown in the east. Alternatively, it could always have been a hunting weapon, only developed for military use by the western successor states.]

You cannot tell me that in this period of strife, the army was as effective as ever!  Bullshit.  The Ursuper generals were struggling to pay, provide, and equip their soldiers

I would say it was. The army of Severus was massive, and the Roman state maintained its warlike capabilities throughout the 3rd and 4th centuries. The reformed armies of Diocletian and Constantine were victorious on all fronts and against all enemies.

The situation you describe of 'usurper generals' etc would fit better with the 5th century. As we discussed before, this was the period and social and political breakdown. State infrastructure collapsed, supply broke down, and the western empire withered. But this did not happen in the 3rd-4th century.

In the east, things continued as before, and the eastern provinces apparently reached their peak of prosperity in the 5th-6th centuries.

Plague does affect society, population and the course of civilisations. But it's one factor among many, and the rapid and constant decline you suggest from the Antonine era is not supported by evidence.

[Robert Vermaat]

The Pilum is so effective...............
Not only that, but Ballista, and their handheld variants, started disappearing.........
The Scutum remains the best riot shield we use today.
I'd also like to add that I think desertion rates were exponentially higher in the Late Empire than during Pax Romana.
We have evidence for crossbows up to around 146ad and then they disappear..........

The pilum is effective for a certain way of fighting. But we have sources that say it became too short to defend against cavalry. Hence its replacement by the longer hasta, several throwing spears and the plumbata. The way of fighting changed, and the pilum became less effective.
The ballista did not begin to disappear for a long time. In your theory it would have been gone before the pilum, due to its far higher technical complexity. It didn't.

The scutum may be a good riot shield but that's not what it was used for in the Roman army. Also, you will notice that modern riot shields are flatter than your idealised scutum. This is because the scutum lacked the ability to overlap the shield of its neighbor, something that was desired more i and more in the defensive fighting style that became more and more favoured from the 3rd c. onwards. The oval and round scuta are far more effective for that sort of fighting. Which was why they became more and more preferred.

If you can provide us with accurate figures for the rate of desertion during both the 'pax romana' (you mean the Principate I think) as well as the later Roman period, that would be marvellous. Until then, I regard this claim as void.

Crossbows did not disappear. they were not used as common weapons like reflex bows, but are far more common as hunting weapons. their role is represented by the amnuballista in the Roman army. The hunting weapons never disappear. What you see as 're-appearing' is neither the hunting weapon nor the manuballistra, but something altogether new, and a response to the plate armour I think (but I'm no expert in that field).

Concluding, I see nothing of the changes as a reaction to some pandemic, but all to evolution in warfare.

[Bryan]

I'll agree that the pila is a cool weapon but you didn't address construction at all, again. You are claiming some great effort goes into making and using pila, I'm saying that is incorrect.

[Fabricius Carbo]

Constructing 20,000 disposal weapons to a certain standard every 3 months or so is definitely not an "easy" task.

Were they 'disposable'?
Why can't they be re used? Even a bent one can be straightened, it doesn’t take much work.

[Bryan]

Pila were definitely not disposable weapons. Shafts would seldom break during a throw, they were thick and sturdy enough. Shafts that bent could be straightened by basic heat treatment by castrum forges after a battle. Those too bent to be straightened properly or the iron too weak could be lofted off at the bend and and then the tip reformed, just leaving a shorter shank.

Considering there was no need for a polished finish on them, the simplicity of the design and manufacturer, pila were one of the easier weapons to make. Easier than a war spear.

[CNV2855]

Regarding mortality numbers, I think we need to look at this through the lenses of similar outbreaks.  



There are no recorded Smallpox outbreaks prior to the Antonine Plague in recorded history, so it's fair to assume that this may be the first transmission of the virus from Asia to Europe.

We know that in populations in which there are no resistances to the virus, mortality approaches 80-95%.  Why would it be any different in this instance, and why are we to assume that the Romans had innate resistance which gave them higher survivability rates?

I'm inclined to believe mortality higher than 50%, perhaps much higher.  Also remember that there were several epidemics decades apart, and the virulence relelentlessy hit society from around 160 to 220 ad, continuing throughout the following centuries.   

Every demographic study I've found concerning the 2nd century shows a massive population decline around 200 AD.   What we need to determine is how sharp that decline is.  

If it's 50% or higher, then that's enough to cripple the state.  If it was 10-15%, perhaps not so much.  Smallpox has never hit a population with innate resistance and had such a low mortality though, and we're almost positive it's Smallpox.

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Nathan, centralized civilization in central Europe did not exist prior to the Black Death.  De-centralized Feudalism was the primary form of government, and inheritance laws combined with the massive amount of death certainly contributed to the fall of the Feudalism and it's replacement.  Find one example where a plague has hit a civilization and that civilization remained intact without changing it's form of government.  

One only has to look at the Plague of Athens, and it's effect on Sparta and Sparta's helot population.  Greece never recovered from the death toll.

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Too much emphasis on the Pila, which compared to Plumbata, were more expensive, sophisticated, and difficult to replace. Instead look at the broad picture, especially that of the evolution of the Ballista and all its variants. Ballista were among the most expensive weapons in Antiquity, and extremely difficult to maintain. During the 3rd Century Crisis, Cheiroballistra which were almost entirely metal began to fade away. Cheiroballista were the Roman equivalent of the crossbow, a weapon that came to dominate Medieval warfare - perhaps more dominant than the English Longbow.

As time continued, even the larger Ballista which were used in siegeworks, city defence, and artillery began to be replaced by Onagers which were rudimentary, cheaper, and less effective. There are some Ballista from the 4th century, but they were slowly phased out due to complexity and cost of maintenance. Prior to the Crisis of the 3rd Century, the Romans were experimenting with a Cheiroballistra mounted cavalry force (mounted crossbowmen).

These weapons (especially the larger versions) were praised for their effectiveness and range (nearly 1,500km!) and very important to the Roman war machine. Why did the handheld variant fall out of use? Eventually, even the larger Ballista and were discontinued and disassembled by the fifth century, only to re-appear 1,000 years later. Roman society could not afford to maintain these complex machines; there's a very good article on just how much maintenance and material went into their production.

Roman gear didn't slowly evolve, it was completely reworked in a very short period of time. We see the disappearance of the Gladius, Pila, Scutum, Ballista, and Segmentata. Five pieces of gear we identify with the Principate legionnaire. Something that drastic happening so swiftly seems to employ a major rift, not a "slow evolution meant to deal with different threats." This was a sudden, swift, and drastic transformation.

If you are to disagree, then explain to me the shortfalls of the Ballista and why a healthy state would discontinue the production of the handheld and siege versions in favor of a simple Onager? Why would such a weapon come to dominate warfare some 1,000 years later when it was reinvented?

Sorry for the edits, I'm quite drunk.

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So... in populations never exposed to smallpox we have 90% mortality. This is the first recorded transmission to Europe. Why do you assume that the Antonine Plague wasn't absolutely devastating? Because it wasn't recorded in literature like other epidemics?

That could in fact be evidence that it was even more virulent and deadly than other epidemics, because the death toll was so high that it prevented historians from recording that period of history. In fact, almost nothing is known from 160-200 AD. It's shrouded in darkness.

After all Cheiroballistra would have been the perfect counter to cavalry forces (which people maintain spurred the revolution of Roman arms).

[Nathan Ross]

Regarding mortality numbers... I'm inclined to believe mortality higher than 50%, perhaps much higher. 

As I mentioned above, it's hard to assess these things, but those who've studied the Antonine Plague have come up with mortality figures ranging from 1-2% to about 15%. Certainly nothing like 50%!

These studies use epigraphy, literary accounts, papyrus evidence of tax payments, coin issues, evidence from later legislation and possible mass burials - they are not guesswork.

One interesting recent study might be this one: Modeling the Antonine Plague. But sadly only the introduction is available in English...

If it's 50% or higher, then that's enough to cripple the state.  If it was 10-15%, perhaps not so much. 

The Roman state was not crippled during this period, so we have our answer to that one!

centralized civilization in central Europe did not exist prior to the Black Death. 

I'm pretty sure it did! Medieval history is not my thing, but large stable monarchies had existed all over Europe for many centuries before the Black Death, while the Italian states had a republican system in place throughout the middle ages. 'Feudalism' was a social system, not a form of government.

Find one example where a plague has hit a civilization and that civilization remained intact without changing it's form of government. 

The Black Death did not cause the collapse of monarchy (or even of individual nation states) in Europe. The Great Plague of 1665 caused no political change in England.

Why do you assume that the Antonine Plague wasn't absolutely devastating?  Because it wasn't recorded in literature like other epidemics?... That could in fact be evidence that it was even more virulent and deadly than other epidemics, because the death toll was so high that it prevented historians from recording that period of history.

In fact, almost nothing is known from 160-200 AD.  It's shrouded in darkness.

On the contrary, we have surviving works by quite a few contemporary writers of the period: Marcus Aurelius himself, the historians Herodian and Cassius Dio, and the medical writer Galen, amongst others. Later historians fill in further details. It's the later period of the 'third century crisis' that's comparatively dark.

Oddly enough, those writers alive at the time make only occasional references to the plague. Marcus Aurelius mentions it three times in his Meditations, while Galen (who was in Aquileia during the outbreak there) says that the troops suffered greatly, but does not imply there was anything unusual about that.

Cassius Dio describes the later outbreak in Rome under Commodus as the worst ever - that's where his figure of 2000 deaths a day comes from, which isn't too huge in a city of c.1 million, and is comparable to previous reported outbreaks under Nero and Titus. Christian writers of the third century refer only to periodic outbreaks of plague, but do not suggest any major lasting depopulation.

It's only later writers - 4th and 5th century - who describe the Antonine Plague as a major catastrophe. It could be that, with the benefit of hindsight, they were able to see a pattern in what had appeared at the time as scattered individual events. But it could be that these later writers had exaggerated a series of relatively minor outbreaks into a major global epidemic. We can't tell either way.

[Bryan]

The plumbata didn't replace the pila. The spear as the primary fighting weapon over the sword, that is what replaced the pila. It had nothing to do with manufacturing cost or anything else you are implying, they simply changed infantry tactics, turning legionnaires away from being javelineer swordsmen to spear men fighting in shield wall formations (something the curved scuta was not good for doing).

Your assumption is that Rome was too hurt from the plague to continue making easy to manufacture weapons like pila or armor like segmentata, while at the same time they increased the length and quality of the sword (spatha), the helmets became more complex and harder to make, and they increased the manufacturing of hamata, which is much more harder in time/labor to manufacturer than segmentata.

[CNV2855]

While I respect your opinion Nathan, I think you're way off and as your numbers don't even begin to make sense, nor are they representative or any research I've read regarding this subject. On top of that, your figures make no sense from a medical point of view when considering the nature of Smallpox.

Conservative estimates for the Antonine Plague are 5 million within the Empire. Perhaps more. The Plague of Cyprian was even deadlier and had an estimated death toll of 15-20 million. Combined (along with starvation, war, and civil strife) the mortality estimates are roughly half of the 65 million Romans who lived at the time. The population had dropped from 65 million from it's height down to 20-30 million, which was where the population remained for centuries.

Smallpox is the deadliest pathogen in human hsitory. It's killed more people than cancer, heart attacks, and all other disease combined. It wiped out 95% of the Americans when introduced by a Spanish slave. How did the Romans, with no immunization to the disease, resist it with such vigor that only 1 in 100 died? That's ridiculous, as Smallpox killed far more than 1/100 in the 18th century just prior to vaccination. Even when it wasn't an epidemic, it killed millions per year for the l ast two thousand years. The Plague of Justinian is probably the deadliest plague per capita in written history, having a higher mortality than the Black Death. It had an profound effect on the Eastern Roman Empire, there's no denying that fact.

So Nathan, please do tell me how the Roman population without any immunity to Smallpox was able to resist it with such vigour?

The demographics, the study of the population between 150AD-300AD tells a story of a massive population drop. A drop of nearly 50%. Fifty percent of the European population disappeared in a very short period of time; war does not account for that. The recent research on the subject in the past couple of years place the introduction of Smallpox as far more devastating than previously supposed.

I don't even want to argue about the effectiveness of solid plate vs maile. I've read plenty of articles from graves from the Viking Age, in which mail was the primary armor, and warriors had no problem penetrating the armor (especially with the Dane axe), literally. It paints a gruesome picture. It was good armor, especially since most blows during fights are overhand cuts as people stab over your shield. Maile still had weaknesses and would fail when hit with particularly powerful blows. One Viking warrior had mail/padding down to his upper thighs, and an axe blow cut through the mail, through both thighs, and severed the mail and bone cleanly. The man was cut in two.

People wore Segmentata during Rome's Golden Age for 250 years. It was obviously very effective armor, and plate is far more effective if you are hit with a powerful swing. Platemail wearing knights were near invulnerable to swordplay; you cannot say the same about mail. People who practice martial arts are able to practice safely with their metal swords when equipped with their plate. Segmentata, though rudimentary compared to High Gothic Plate, provided a degree of protection that just wasn't afforded to the more flexible armors.

You can not say that mail was a superior armor. It doesn't make sense in any context, especially a historical one. The more interesting question is whether or not Segmentata was clearly superior to mail? Probably not. I think it would depend on where the soldiers were placed in the rank and file, if they were archers, deployed in the center/flanks, or other circumstances. Also the arms of their opponent may come into play, with Segmentata being used against the more heavily armed nobility, while mail was clearly superior to spearmen.