How sure are we of pre-mechanized army sizes?

February 3, 2020 11:05 AM

The sizes given for armies in the pre-mechanized era frequently set off my B.S. detector. For example, Napoleon’s 685,000 soldiers marching on Moscow would have required 1000 tons of food daily and would have left a swath of 365 tons of excrement per day in their wake.

Continuing with Napoleon’s march on Moscow as an example, I realize the army was at least at first spread across a significant area but the further they went the tighter they became. And yes, if you go by the official numbers the whole fiasco resulted in the deaths of 400,000 French soldiers but that means that even at the end 285,000 people were being fed, clothed, and policed using horses and carts.

The numbers for this (for this as well as many other historical campaigns) seem like the sort of exaggerations that show up in retellings and are encouraged by governments to make themselves look good. How much documentation exists?

posted by Tell Me No Lies to Grab Bag (16 answers total)

Someone else can hopefully explain where the numbers come from. (This was a modern war— we probably have the payroll records.) But we can compare these numbers to other wars.

Note that Napoleon, at this point, had conquered most of Europe. Only half of his army was French. Half a million men is by no means a stretch for a continent-wide power. Also compare the total population of Europe in 1815: 200 million.

World War I: the German army alone began the war with 4 million men. The US alone sent 2 million soldiers to Europe, of which half saw battle.

In the Civil War, the US (North) had a million soldiers under arms, the South half a million.

By the end of the Iran-Iraq war, each side had at least 600,000 soldiers, and Iraq only had about 13 million people.

FWIW, the ancient Roman army was about 250,000, at a time when the empire had about 40 million people.

Finally, if your instinct is that Napoleon's operation was a logistic disaster... well, you're right, it was! His numbers spectacularly decline throughout: half a million at the start, 200,000 on the march to Moscow, 100,000 when he took the city, 50,000 when he retreated to Smolensk.
posted by zompist at 11:39 AM on February 3, 2020

I don't know the answer to your specific question about how we know the size of that army, but here's how you can find out.

What you are interested in is Historiography - which is the study of how and why historians know what they say they know (and how that changes over time). Wikipedia has a section in their page on Military history devoted to Historiography of Military History that describes some of the issue particular to that domain.

For a given army or conflict, Wikipedia usually has a section on historiography of that thing. For example in the article on Napoleonic Wars, there's a section for historiographical further reading. The French Invasion of Russia page also has a very large and well-referenced section on logistics, and another on historiography.

I personally would caution against assuming that number is inaccurate or propaganda just because you find it hard to understand the how to deal supply chains and logistics on a massive scale prior to mechanization. Highly qualified people have spent their entire careers analyzing that campaign, and refining estimates for greater veracity is of primary concern. Also it wasn't really all that long ago, to a historian.

If you want more on Napoleon's logistics, here's a nice write-up by a USAF major outlining some of the methods and historical context surrounding mobilizing armies of that size:
Napoleon’s Logistics; or How Napoleon Learned to Worry about Supply. It contends that logistics weren't his only problem, and that he wasn't so ignorant of the demands of logistics as some historians have suggested.
posted by SaltySalticid at 11:45 AM on February 3, 2020

Moderately sure. As mentioned in Wikipedia's Order of battle of the French invasion of Russia:

Figures on how many men Napoleon took into Russia and how many eventually came out vary rather widely.

• [Georges] Lefebvre says that Napoleon crossed the Neman with over 600,000 soldiers, only half of whom were from France, the others being mainly Germans and Poles.
• Felix Markham thinks that 450,000 crossed the Neman on 25 June 1812, of whom less than 40,000 recrossed in anything like a recognizable military formation.
• James Marshall-Cornwall says 510,000 Imperial troops entered Russia.
• Eugene Tarle believes that 420,000 crossed with Napoleon and 150,000 eventually followed, for a grand total of 570,000.
• Richard K. Riehn provides the following figures: 685,000 men marched into Russia in 1812, of whom around 355,000 were French; 31,000 soldiers marched out again in some sort of military formation, with perhaps another 35,000 stragglers, for a total of less than 70,000 known survivors.

Whatever the accurate number, it is generally accepted that the overwhelming majority of this grand army, French and allied, remained, in one condition or another, inside Russia.

posted by zamboni at 11:47 AM on February 3, 2020

For medieval and classical accounts, it gets a lot fuzzier. There has been some work in attempting to test and reconcile historical accounts of army size with what was actually possible - see things like Logistics of Warfare in the Age of the Crusades.
posted by zamboni at 12:11 PM on February 3, 2020

I remember reading somewhere that Napoleon was notorious for not feeding his army. They were expected to scavenge from whatever local populace they were marching through.
posted by SemiSalt at 12:13 PM on February 3, 2020

Yes, I think you are imagining something like a modern highly-disciplined army with a tight supply chain. These soldiers would in many cases have literally billeted down among the local villagers. They were perpetually undersupplied with everything. In fact, early modern armies were notorious for "camp followers," various enterprising individuals who might follow the army for some distance providing supplies and, ah, services that one would expect a modern army to supply its members (except for one very popular one). And, um, modern hygiene wasn't so much of a concern then. ANY war prior to, hm, mid-20th-century was a logistical (and hygienic!) disaster for these reasons. (And most of the more recent ones devolved into one, sooner or later, given the chance.)
posted by praemunire at 12:27 PM on February 3, 2020

Maybe here, SemiSalt: Though one of the greatest military generals of all time, Napoleon was surprisingly negligent about feeding his army. [...] During the Italian campaign, in which the 27-year-old Napoleon made his name as a general by defeating a much larger Austrian army and its allies, his men simply foraged off the land or plundered nearby villages — a common military practice then. (Appetite For War: What Napoleon And His Men Ate On The March, NPR.org, June 25, 2018)

Per the article, his soldiers died from thirst and/or starvation during certain campaigns.
posted by Iris Gambol at 12:32 PM on February 3, 2020

I don't know why they call it "surprisingly" when they note a couple of sentences later that this was a common military practice. Soldiers absolutely could and did die of starvation, thirst, the most modest but untreated wound, getting robbed and dumped in the river by the locals...
posted by praemunire at 1:04 PM on February 3, 2020

praemunire, my impression is that it's surprising due to the unusually severe way the practice played out, especially given Napoleon's reputation as a brilliant tactician. Plundering in Italy, in springtime, was simple; as the result of one food and water shortage (during a 10-day forced march from Cairo to Syria), ... soldiers began to commit suicide. A stampede at a solitary well killed 30. The desperate men dug sea sorrel, ate it and developed dysentery.

Specifically to the Moscow reference in your question, OP (eponysterical, btb): The Grande Armée was annihilated more by starvation and cold than by the Cossacks. With absolutely no food supplies and temperatures at 20 below zero, the ravenous men ate horseflesh seasoned with gunpowder, often fighting over a fallen horse's flank to tear out its liver, sometimes even before ascertaining whether the animal had died.
posted by Iris Gambol at 2:29 PM on February 3, 2020

To further confound evidence, the bones of dead soldiers were “dug up from the battlefields … and used as fertiliser”
(tw: pretty much everything.)

ISTR one of the big British agrochemical companies started out as a bone grinder, but the name eludes me.
posted by scruss at 2:40 PM on February 3, 2020

praemunire, my impression is that it's surprising due to the unusually severe way the practice played out, especially given Napoleon's reputation as a brilliant tactician.

But...it's still not? Because all armies struggled with these issues. Take anyone noted as a brilliant tactician in the early modern period and you're likely to find him struggling through a quagmire of incompetent logistics. It played out worse on the freezing Russian steppe than it might have in, say, southeast England in summer, but the unbelievably low level of skill and resources devoted to these issues was just about ubiquitous.
posted by praemunire at 3:09 PM on February 3, 2020

I think this is getting a little derail-ey, but the last link SaltySalticid's post does explain a lot of this, and I'll do my best to summarize.

The Italian campaign mentioned in the NPR piece was at the beginning of his career when he was handed 90,000 starving men, undersupplied by the revolutionary French government's mismanagement, and he basically said "there's some rich cities that way, let's go get 'em and have something to eat."

After that, Napoleon was really innovative in managing logistics. There's every reason to suspect Napoleon's numbers are accurate since one of the reasons he was so successful is because he implemented a strong military bureaucracy for keeping track of everything and for feeding and amassing large offensive armies. Trying to add systematic deception on top of that would have been extremely difficult when no one had quite got the basics down.

And the reason Napoleon's army lost in Russia is because he took a gamble that he could load down his soldiers with 2-3 weeks of food so he could gather the biggest concentration of force the world had ever seen in the hopes of catching the Russian army in one quick and decisive battle. All the Russian army had to do to win was eat all the food and escape and leave the countryside to be ravaged by the oncoming army, which they did.

The reason why 685,000 soldiers feels like an absolutely insane and ridiculous number of people for the time is because it was an absolutely insane and ridiculous number of people for the time.

But it's not like there wasn't a plan. It just didn't work. The fact that Napoleon could even attempt it is testament to his army's logistical capabilities. Which is evidence that they probably had to be taking pretty accurate notes and not making up big numbers that sounded good.
posted by Zalzidrax at 3:27 PM on February 3, 2020

Highly qualified people have spent their entire careers analyzing that campaign, and refining estimates for greater veracity is of primary concern.

Yeah, that's sort of my point. No one spends their career on something that was well understood before they got started. The question for me is how well is it understood now.

Thank you for the pointers. I had never heard of Historiography although of course it exists. I've got some reading to do.
posted by Tell Me No Lies at 6:26 PM on February 3, 2020

For the medieval period, army sizes are very hard to calculate and were often exaggerated by contemporary chroniclers. A case in point is the Battle of Towton (1461), often described as 'Britain's bloodiest battle', with claims that there were between 50,000 and 80,000 men in the field, and an estimated 28,000 casualties (equivalent to 1% of the entire population of England at the time). These figures are implausibly high, and a careful reading of the Wikipedia article will show that (a) the contemporary sources are very inadequate, and (b) estimates of casualties vary enormously from one source to another. So you are right to be sceptical.

From the sixteenth century onwards, however, we can start to be much more confident about army sizes. This period witnessed what some historians have called a Military Revolution, with massive changes in the nature of European warfare. This led to the development of the so-called fiscal-military state, in which governments started to raise much bigger sums in taxation in order to create much larger armies. This meant that governments needed to know, with a reasonable degree of accuracy, how many soldiers they had in their armies and how much it cost to keep them there. Result: bigger bureaucracies and better record-keeping.

Historians have now started to drill down into the archives to try and come up with accurate figures for the size of European armies. For an example, see John A. Lynn's article 'Recalculating French Army Growth during the Grand Siècle, 1610-1715', from 1994. Briefly summarised, Lynn's argument is that the contemporary estimates of army size generated by the French central government for the purpose of financial planning (known as contrôles) are probably an over-estimate. However, we have other documents known as review reports and étapes routes which give us a much more accurate picture of the situation on the ground:

Review reports were prepared by military bureaucrats for administrative reasons, as when distributing pay and rations to soldiers. Troops on the road traveling from place to place carried routes, documents that stipulated their route and the stops they were allowed to make along the way. At each stop they were entitled to rations and lodging, so the routes stated exactly how many men of what ranks were to be fed and housed. By their nature, review reports and routes dealt only with individual units or small groups of units, rather than with an entire army, but they will be put to a broader use here. Because the actual sizes of units can be calculated from reviews and routes, these numbers can be used to estimate the percentage of regulation strength actually present under arms. Gross statements of army size can then be discounted by this percentage to yield a reasonable estimate of real troop numbers.

So that's the short answer to your question: yes, the documentation exists, and yes, the research has been done. Lyon suggests that the 'paper figures' for army size have to be heavily discounted (in some cases by as much as 50-60%) to arrive at accurate estimates of actual troop strength. That may seem like a big reduction. But the figures are so high to start with that, even when you discount them, you still have armies of massive size. During the War of the Spanish Succession, for example, Lyon suggests a 'theoretical high' of 380,000 which, when discounted, yields a more accurate figure of 255,000. By any standard that is a staggeringly large fighting force.

If you want to pursue this further, I recommend Martin van Creveld's Supplying War: Logistics from Wallenstein to Patton, the first and still the best modern historical study of military logistics. For me, the big takeaway from Creveld's book is that -- counter-intuitively -- it was much more difficult to provision a static army than a mobile one. The density of European population and agriculture meant that it was quite easy to feed an army as long as it kept on the move. But if the army came to a stop (e.g. during a siege), supplies of food (and, crucially, fodder for horses) very quickly started to run out. Napoleon's genius was to realise this and adapt his military strategy accordingly:

Napoleon realized that it was the eighteenth-century predilection in favour of siege warfare that led to endless logistic difficulties. As he himself was able, thanks to the size of the forces under his command, to do without sieges, he rendered the logistic apparatus of the eighteenth century largely superfluous. Hence the explanation for a fact which, at first sight, appears incomprehensible. Although the technological means at his disposal were by no means superior to those utilized by his predecessors -- indeed, he was rather conservative in this field, rejecting new inventions and doing away with some old ones -- Napoleon was able to propel enormous forces right across Europe, establish an Empire stretching from Hamburg to Sicily, and irreparably shatter an entire (old) world.

posted by verstegan at 8:59 AM on February 4, 2020

The Logistics of the Roman Army at War by Jonathan Roth may explain this for Romans, although I can't be 100% sure because I'm only a couple of chapters in.

He goes into some detail about assumptions that have been made about various facets of military logistics in the era, such as how many calories per soldier you need to ensure healthy, reasonably well-fed troops, and how those numbers are arrived and and why they are or are not good numbers, and why he thinks one set of numbers is the most likely. I assume he continues that through the rest of the book.
posted by telophase at 11:39 AM on February 4, 2020

Tangential, but I can't resist an opportunity to link Minard's graphic of Napoleon's advance and retreat from Russia.

Amazing piece of visual design, conveying position, strength of army and temperature.
posted by MattWPBS at 5:42 AM on February 5, 2020