Wondering About Population/Army Sizes

[Flickerdart]

Okay, point. Doesn't change my conclusion, though!

Yeah, I'm not disagreeing with your conclusion - an infinite food machine is always worth it if you're able to secure a massive loan somehow. That's a fairly big if, though, unless your setting has advanced financial instruments.

I'm also not sure how the demographics will look - smaller villages (which is most of the villages) still need to farm because the pot is unprofitable, and people above "dirty peasant" level would want better food than just gruel, which creates demand for real farming. You also need peasants to do something, and teaching them skills takes effort. Plus, you need a market for any goods they produce. Free food might just result in a population boom of...more farmers.

[Yukitsu]

It's also a custom magic item which by RAW aren't guaranteed. Most economy breaking ones shouldn't be considered that likely in a setting.

[ExLibrisMortis]

Yeah, I'm not disagreeing with your conclusion - an infinite food machine is always worth it if you're able to secure a massive loan somehow. That's a fairly big if, though, unless your setting has advanced financial instruments.

I'm also not sure how the demographics will look - smaller villages (which is most of the villages) still need to farm because the pot is unprofitable, and people above "dirty peasant" level would want better food than just gruel, which creates demand for real farming. You also need peasants to do something, and teaching them skills takes effort. Plus, you need a market for any goods they produce. Free food might just result in a population boom of...more farmers.

Loans like that have been around since Roman times. An interesting quote: "[...] a credit crisis in 33 AD that put a number of senators at risk; the central government rescued the market through a loan of 100 million HS made by the emperor Tiberius to the banks" (100m silver pieces? a legionary would earn 900 HS/year at that time, with half deducted for costs). It still depends on your setting, but the GP limit for a metropolis is 100.000 gp (25k+ population), and for a large city it's 40.000 gp (12k+ population). I think that most settings will have this available. Making the gruel taste nice is a simple matter of adding common herbs, which won't cost very much. There will still be people farming, but for expensive crops, like coffee and tea, cotton, fruits, spices and so on.


The demographics are more interesting. If food becomes nigh-worthless, some other activity must be the just-about-profitable thing that "dirty peasants" can do to get by. In our current economy (in western countries), it mostly involves things that are hard or expensive to automate, work in factories and (seasonal) work on farms, cleaning and so on. Screwing caps on toothpaste tubes, á la Charlie Bucket's father. However, in pre-industrial times, it might have been spinning (for clothes), carrying heavy stuff, and building. Mining is a good option, as you need to get the gold for magic item creation from somewhere.


Edit: In fact, I should think that most of the economy would be focused on magic item creation, as that wholesale replaces the entire modern manufacturing industry, from cars to canned food.

[Flickerdart]

Loans like that have been around since Roman times. An interesting quote: "[...] a credit crisis in 33 AD that put a number of senators at risk; the central government rescued the market through a loan of 100 million HS made by the emperor Tiberius to the banks" (100m silver pieces? a legionary would earn 900 HS/year at that time, with half deducted for costs). It still depends on your setting, but the GP limit for a metropolis is 100.000 gp (25k+ population), and for a large city it's 40.000 gp (12k+ population). I think that most settings will have this available. Making the gruel taste nice is a simple matter of adding common herbs, which won't cost very much. There will still be people farming, but for expensive crops, like coffee and tea, cotton, fruits, spices and so on.

The Romans had a lot of things that were lost in medieval times.

Besides, just because the government of the Roman empire can take a loan to save the economy doesn't mean that some podunk mayor can do so for a pot that makes gruel.

As for the GP limit, just because the city might have the item for sale doesn't mean that it has an easy way of getting loans for it. There will also be remarkably few cities of that size in a setting that looks anything like medieval Europe.

The demographics are more interesting. If food becomes nigh-worthless,

Except it doesn't - basic nutrition becomes easy, but that doesn't stop anyone from wanting a steak or a pie.

some other activity must be the just-about-profitable thing that "dirty peasants" can do to get by. In our current economy (in western countries), it mostly involves things that are hard or expensive to automate, work in factories and (seasonal) work on farms, cleaning and so on. Screwing caps on toothpaste tubes, á la Charlie Bucket's father. However, in pre-industrial times, it might have been spinning (for clothes), carrying heavy stuff, and building. Mining is a good option, as you need to get the gold for magic item creation from somewhere.

Edit: In fact, I should think that most of the economy would be focused on magic item creation, as that wholesale replaces the entire modern manufacturing industry, from cars to canned food.

You can't really make an economy out of magic item creation, since it's basically a one-man job with a very small market (very wealthy nobles and traders, governments, and adventurers).

[Faily]

This, the water in much of Europe was really, REALLY unsafe to drink and mead/beer and wine was needed as both the alcohol and the boiling process killed most of the bad things in it and was therefor much safer to drink.

Purify water/create water takes the need and destroys it. This would mean that Beer and Wine and such would only exist for 'recreation' as it does today, and with the low pay of commoners it would be something only the rich would tend to drink. And that is only IF they came into existence in the first place, they are after all 'spoiled' and if clerics are running around doing such things all the time they might just 'fix' it before its other properties are discovered.

I mean it should show up as a poison if they used detect poison on it after all.

That people didn't drink water in the Middle Ages is pretty much a myth. It's a myth that I wish could GDIAF already.

While water-sources in urban areas had a higher chance of pollution, water was still widely consumed across Europe in the Middle Ages. But just like today, people liked to drink something else than just plain tasteless water and just like today people rarely talked about "this great water".

Most cities and large towns invested greatly in securing good sources of water. The cleanest water was used for consumption, cooking and making other beverages (such as ale or wine), the dirtier water was used for other purposes, like being stored up to put out fires.

EDIT: So basically, a caster using Purify Food and Drink ensures that more of the water can be consumed and used for food and drink, AND is a huge life-saver in case of a siege when a water-supply would likely be sabotaged with simple poisoning (like dumping feces or bodies in the water-source). As it is a 0-level spell, it could also be a worthwhile investement for a settlement in a magical society to make some magic item that continously purifies a water-source.

Sources:
Squatriti, Paolo, Water and Society in Early Medieval Italy, AD 400-1000 (Cambridge, 1998)
Hagen, Ann, A handbook of Anglo-Saxon food : processing and consumption (Pinner, 1992)
Kucher, Michael, ‘The Use of Water and its Regulation in Medieval Siena’, Journal of Urban History, Vol.31:4 (2005)
McNeill, John T. and Gamer, Helena M., Medieval handbooks of penance : a translation of the principal “libri poenitentiales” and selections from related documents (New York, 1965)

[ExLibrisMortis]

The Romans had a lot of things that were lost in medieval times.

Besides, just because the government of the Roman empire can take a loan to save the economy doesn't mean that some podunk mayor can do so for a pot that makes gruel.

As for the GP limit, just because the city might have the item for sale doesn't mean that it has an easy way of getting loans for it. There will also be remarkably few cities of that size in a setting that looks anything like medieval Europe.

Except it doesn't - basic nutrition becomes easy, but that doesn't stop anyone from wanting a steak or a pie.

You can't really make an economy out of magic item creation, since it's basically a one-man job with a very small market (very wealthy nobles and traders, governments, and adventurers).

Banking - rather, lending money, not neccessarily modern banking - is not one of the things lost after the fall of the Roman Empire. The Code of Hammurabi has laws on interest, start reading at law 100 (I know that's pre-Roman, before you ask ). The Quran prohibits the lending of money against interest - that's not because it didn't happen at the time. The Knights Templar acted as banking service across Europe and in the Holy Land. Plenty of examples.

As for city size, first an atypical example: "From the 9th through the end of the 12th century, the city of Constantinople, capital of the Byzantine Empire, was the largest and wealthiest city in Europe, with a population approaching 1 million" (note that that should be 20-40% of that, according to the next list, but okay). This list may be interesting as well - it tells us that cities of 12000 people and up have existed since 3000 BC, if not earlier. By 2000 BC, cities with 25.000 people exist. By 1000 BC, a few cities hit 100.000 - Babylon, Memphis, Thebes, some that I don't recognize (bad Eurocentrism, bad!). By 0 AD, Rome apparently had 800.000 to 1.000.000 inhabitants. Around 1000 AD, the table lists dozens of cities with more than 50.000 people - likely, a lot of the smaller ones are omitted for space reasons.

Now, I'm not suggesting that you're dropping these cities all over the place. But I am suggesting that most settings have these places, and I am suggesting that the rules don't tell you about cities and metropolises for no reason, and that NPCs will visit the magic mart in those places. If you're looking to purchase a 30.000 gp item, you're willing to cart it a few weeks back to your town to get it. Compare it to a church bell. You buy one every couple of centuries, and not a lot of people make them, but a lot of places have them. If you can't get a loan, you can always save up. People will manage.

As for magic item creation being a one-person job: yes and no. Somebody still needs to forge all those enchantable ten-cubic-metre kettles, gather and prepare material components, research and copy those spells and whatnot. Most of the people in the magic item business won't be artificers, but rather the people supplying and taking care of artificers (who can't do anything but light activity for 16 hours a day). Lots of people will be in the diamond mining business, the gold mining business, the 'incense, inks and oils' business. Expeditions to the Elemental Plane of Earth to gather diamonds - the plane shift item only works once a week, so be in time or wait for the next run (and hope your supplies don't run out). Expeditions to slay dangerous animals to pick up power components. That sort of thing.

The market for magic items isn't small if you look at it that way, either. It's not like the demand for 'mechanical things' or 'fighting things' was small in medieval times. Why should the demand for 'magical things' be any different? You can be sure that a huge city with half a million people has an item of control weather to keep hurricanes out of the harbour - something your medieval mechanic would be hard-pressed to provide, proving the worth of magic. Any emperor worth his salt sets up a mail system using ring gates - expensive as hell, but the coffers will cover it, and it sure beats walking/riding all that distance (though imps are cheaper, if you're LE). Only a couple of artificers in the world can build high-end items like that (adventurers seem to get them just fine, though), and those craftsmen are respected like an Archimedes or a Michelangelo.

And finally, I believe I adressed the gruel/flavour issue. Yes, people will still farm for luxury products, and things to spice up the base food. Most of the calories will still come from the kettle - just like modern-day food has large parts of bread, potatoes, rice, pasta and so on. This kettle isn't producing horrible muck, it's producing "simple fare of your choice - highly nourishing, if rather bland". Boiled rice and spinach, with a side of tofu*, that kind of thing (assuming 'highly nourishing' means 'balanced diet'). Nothing you can't fix up with minimal effort (and since you decide what it is, you know exactly what it needs to be tasty, too!). Soy sauce production would soar.

Of course, a kettle can be used to feed livestock - one horse (presumably a cow qualifies too, or any large creature) replaces three humans. Not great for grazing stock, but if you've got these kettles in numbers, why not. Bio-industry made easy.

If you don't want to play in a setting like this, fine. But the game rules do support it - your objects notwithstanding - even if you consider the huge price difference between first-level commoners' meals and high-level magic items.


*Which I prefer over a steak, thank you very much. Steaks - talk about bland food.

[Faily]

Read ExLibrisMortis' post...

WHY IS THERE NO LIKE BUTTON?!

*ahem*

Just very glad to see someone actually know their medieval history and society.

(Also, since I'm running a Kingdom in Pathfinder... totally investing in magic kettles to feed the population! )

[ExLibrisMortis]

Read ExLibrisMortis' post...

WHY IS THERE NO LIKE BUTTON?!

*ahem*

Just very glad to see someone actually know their medieval history and society.

(Also, since I'm running a Kingdom in Pathfinder... totally investing in magic kettles to feed the population! )

Thank you very much. May I put that in my signature?

I don't know much about history, but my father is a historian - he doesn't like the 'dark ages' stereotype - and wikipedia is a thing (I like).

[Flickerdart]

Now, I'm not suggesting that you're dropping these cities all over the place. But I am suggesting that most settings have these places, and I am suggesting that the rules don't tell you about cities and metropolises for no reason, and that NPCs will visit the magic mart in those places. If you're looking to purchase a 30.000 gp item, you're willing to cart it a few weeks back to your town to get it. Compare it to a church bell. You buy one every couple of centuries, and not a lot of people make them, but a lot of places have them. If you can't get a loan, you can always save up. People will manage.

A church bell is of little use to, say, bandits, but a 30kgp kettle is awesome. Overland travel is dangerous and slow. A few weeks? Try months.

As for magic item creation being a one-person job: yes and no. Somebody still needs to forge all those enchantable ten-cubic-metre kettles, gather and prepare material components, research and copy those spells and whatnot.

Actually, by the rules, crafting a magic pot does not require that one first possess a non-magic pot. Curiously, there is no way to craft a material components bag (Craft: Alchemy, maybe?).

[Faily]

Thank you very much. May I put that in my signature?

I don't know much about history, but my father is a historian - he doesn't like the 'dark ages' stereotype - and wikipedia is a thing (I like).

Be my guest.

I studied art and culture history at school, but am more of a hobby-historian and one who also greatly enjoys Wikipedia and other websites dedicated to accumulating knowledge on these topics.

[Karl Aegis]

If your food needs are taken care of you more onto cash crops for farming. Sugar, cinnamon, hops, tobacco, cotton, etc. You move your "dirty peasants" into the "plantation slave" profession. Hope you can still afford salt. Salt makes travel better.

[Nibbens]

I don't know about 5 percent, but I've heard of a 1% standing army and 1% police force. During a wartime scenario, the police can be pulled into the army quickly. With more time to conscript during a full-time fight or death scenario approximately 25% of the citizens would be of fighting material.

A town of 1000 would have 10 in their "army" and 10 in their police force. This might translate into 10 in a police hierarchy, and 10 deputies on the lowest rung. Or 1 sheriff, 9 guards, and 10 deputies. Heck you could even do 10 guards, and 10 mercenaries that the guards can hire on the spot. It all depends on how you want to spin it.

Regardless, in a town of 1000, you may be looking at NPCs level 1-3 with a few outliers in the 4 to 5 range. So the fight should be as someone said earlier. The guards are giving the townspeople a few extra seconds to escape the PCs murderous rampage.

[5ColouredWalker]

A church bell is of little use to, say, bandits, but a 30kgp kettle is awesome. Overland travel is dangerous and slow. A few weeks? Try months.


Actually, by the rules, crafting a magic pot does not require that one first possess a non-magic pot. Curiously, there is no way to craft a material components bag (Craft: Alchemy, maybe?).

-1 Sure, the kettle might be awesome... For a bandit army, or someone who can hold it ransom in the middle of the town. However it's really damn big, do you as a bandit want to try carting off something that you'll need a wagon to move, and will have everone trying to hunt you down and kill you so they can get the kettle back so they don't starve?
Might want to rethink your bandit idea.

-2 No, they just need thousands in undefined materials... Oh look, the DM just defined them and there's a massive industry supporting them. Well how about that.


Tales of Mu [NSFW] has a great explanation at one point for why the tippyverse/rational can not happen to it despite being modern and with magic items everywhere. First it shows a thought experiment, the standard guess the rule using numbers, and it turns out without cheating or lying, random could be done because the rule was 'Any three numbers I agree meets the rule.'
Then, it's brought up that that's the way their world works.

For example, there's a dome that's infanantly large around the world that is their sky... But outsiders can fall from it to the ground safety, and in times of great need, the world has let someone climb on top of the dome. However if you start asking the world to do it regularly, the world pimp slaps you and suddenly there's a rather blighted area where some 'scientist wizard' used to be, and now all the remaining scientists either aren't very serious, or look at all the scorch marks and guess while trying not to join them.

This way, you can have a modern world in the DnD verse using magic that isn't the tippyverse.

Sure, the kettle idea could work and is indeed genius, but your GM/World could be one that likes medieval stasis, and as such your plane might just up and kill you if you try to industrialize it. Or it might change the rules slightly so the magic doesn't work the way you intended. Perhaps your ketle instead just turns into a item of everlasting rations + everful mug that feeds a number of people by taking your gold, deducting 350+[250*1.5], and then dividing the rest by [350*1.5+250*1.5].

[Jay R]

In a peaceful town of 1,000 adults, there's probably 10-20 guards. But if the town is under attack, there are 500+ people fighting back.

[atemu1234]

That's what Prestidigitation is for.
As for cost...we assume the party's Cleric isn't charging his allies.

Hey, a Cleric's gotta make a living...

[SowZ]

In a peaceful town of 1,000 adults, there's probably 10-20 guards. But if the town is under attack, there are 500+ people fighting back.

Maybe 10-20 people who are armed and know how to fight, but certainly not 10-20 professional soldiers/lawmen.

[ekarney]

What about in settings that do not only allow for, but actually contain standing armies. Such as the Purple Dragons of Cormyr in 3.5, it states that Nobles are expected to join.
There's also a 2 and a half year service program they've made, where the recruit spend their first 6 months patrolling and training.
How many people could be in that army? (Including a standing/professional army, militia and guardsman)

[SowZ]

What about in settings that do not only allow for, but actually contain standing armies. Such as the Purple Dragons of Cormyr in 3.5, it states that Nobles are expected to join.
There's also a 2 and a half year service program they've made, where the recruit spend their first 6 months patrolling and training.
How many people could be in that army? (Including a standing/professional army, militia and guardsman)

The Medieval Period saw very little in the way of standing armies, so let's go back and look at Rome. At the height of the Roman Empire? When the standing army was gargantuan and the Empire the most vast? We're looking at a population likely close to 100,000,000. Maybe more. And we are talking about a professional military of less than half a million. This army compromised anywhere from 0.3% to 0.7% of the population. Likely less than half of one percent. This number can double if we are talking about their equivalent of reserve troops, or troops rallied for specific campaigns. But we are talking standing armies, yes? And we are talking about an economy that was heavily structured around keeping the military going. Nothing about the Roman economy wasn't somehow connected back to the army. So if we assume Cormyr is equally military focused and we assume that with magic and such they might be able to afford more troops than Rome, I would still be very surprised if the percentage of the populace in the military was more than 2%.

But many of those will be in training at any given time or in the field fighting battles. Or else focused in metropolitan population centers. Or being used to do something useful, (assuming there is no one to fight,) and are building roads and buildings and such. There aren't going to be a score men spared to patrol a small hamlet. Not unless there is some reason to believe said village is in danger of being raided by an impending enemy force.

[ekarney]

The Medieval Period saw very little in the way of standing armies, so let's go back and look at Rome. At the height of the Roman Empire? When the standing army was gargantuan and the Empire the most vast? We're looking at a population likely close to 100,000,000. Maybe more. And we are talking about a professional military of less than half a million. This army compromised anywhere from 0.3% to 0.7% of the population. Likely less than half of one percent. This number can double if we are talking about their equivalent of reserve troops, or troops rallied for specific campaigns. But we are talking standing armies, yes? And we are talking about an economy that was heavily structured around keeping the military going. Nothing about the Roman economy wasn't somehow connected back to the army. So if we assume Cormyr is equally military focused and we assume that with magic and such they might be able to afford more troops than Rome, I would still be very surprised if the percentage of the populace in the military was more than 2%.

But many of those will be in training at any given time or in the field fighting battles. Or else focused in metropolitan population centres. Or being used to do something useful, (assuming there is no one to fight,) and are building roads and buildings and such. There aren't going to be a score men spared to patrol a small hamlet. Not unless there is some reason to believe said village is in danger of being raided by an impending enemy force.

So in the interest of not dealing with fractions a flat 2% of 1,000,000 (Cormyr's estimated population) we'd be looking at a total size of ~20,000, I guess if we included the household guards of nobles as exterior entities and the inclusion of out of kingdom mercenaries we could probably jump that to ~25,000

Damn, this puts a spanner in my campaign works, if a town with 15,000 people in it is threatened by war by a nation with a 20,000 army you'd think they'd surrender right away.
Damn, I need to figure some things out then.

[Flickerdart]

Towns typically don't fight wars. That town should have backup from its sovereign lord - and if it doesn't have one, it will soon, because of the aforementioned 25,000 soldiers.

But it's hardly a big deal - towns were occupied all the time. If you don't have city walls and you don't have an army ready for a pitched battle, you're going to be taken over. Whether or not the invaders can keep the town by the time the defending army comes around is another story.

[SowZ]

Towns typically don't fight wars. That town should have backup from its sovereign lord - and if it doesn't have one, it will soon, because of the aforementioned 25,000 soldiers.

But it's hardly a big deal - towns were occupied all the time. If you don't have city walls and you don't have an army ready for a pitched battle, you're going to be taken over. Whether or not the invaders can keep the town by the time the defending army comes around is another story.

Shoot, a band of twenty armed bandits could take over a village, demanding tribute and food, and it is unlikely they'd get much resistance as long as they weren't going crazy and killing people and such, (which why would they?)

[Yukitsu]

The Medieval Period saw very little in the way of standing armies, so let's go back and look at Rome. At the height of the Roman Empire? When the standing army was gargantuan and the Empire the most vast? We're looking at a population likely close to 100,000,000. Maybe more. And we are talking about a professional military of less than half a million. This army compromised anywhere from 0.3% to 0.7% of the population. Likely less than half of one percent. This number can double if we are talking about their equivalent of reserve troops, or troops rallied for specific campaigns. But we are talking standing armies, yes? And we are talking about an economy that was heavily structured around keeping the military going. Nothing about the Roman economy wasn't somehow connected back to the army. So if we assume Cormyr is equally military focused and we assume that with magic and such they might be able to afford more troops than Rome, I would still be very surprised if the percentage of the populace in the military was more than 2%.

But many of those will be in training at any given time or in the field fighting battles. Or else focused in metropolitan population centers. Or being used to do something useful, (assuming there is no one to fight,) and are building roads and buildings and such. There aren't going to be a score men spared to patrol a small hamlet. Not unless there is some reason to believe said village is in danger of being raided by an impending enemy force.

The highest I've ever seen for Rome was 60 million people living within their borders, only about 10 million of them living in Italy. Officially, the Roman Empire seems to have had about 450,000 troops. Given this was at a period of relative peace though, it seems likely that if an adversary arose at that time, the Romans could have raised more.

I'm also trying to figure what the percentage of that population was slaves or conquered peoples that could not qualify for the army. I'm not exactly certain whether or not they could have raised more if those slaves were free or if having slaves required more military presence by such a huge margin that it levels out or favours the army. Given how many slaves were in the city of Rome itself which wasn't defended by the legions directly it seems likely that full time military were not used to counter slave populations.

Those numbers may also fail to include the Vigiles which were the professional police of Rome.

By percent though, the Roman Empire had fewer men in the legions than they had during the height of the Republic. At the height of Roman military power in the Republic they managed over 700,000 legionaries with a population less than half that of the Empire. That was after the Marian reforms where a legionary was a professional soldier as compared to the Hastati civil soldier.

[Jay R]

In a peaceful town of 1,000 adults, there's probably 10-20 guards. But if the town is under attack, there are 500+ people fighting back.

Maybe 10-20 people who are armed and know how to fight, but certainly not 10-20 professional soldiers/lawmen.

10-20 people who are armed and know how to fight, and another several hundred people with bows or boarspears who know how to hunt.

If it's an internal town, with only fields around in all directions, maybe not. But people who live in a frontier village know how to live on a frontier.

[SowZ]

The highest I've ever seen for Rome was 60 million people living within their borders, only about 10 million of them living in Italy. Officially, the Roman Empire seems to have had about 450,000 troops. Given this was at a period of relative peace though, it seems likely that if an adversary arose at that time, the Romans could have raised more.

I'm also trying to figure what the percentage of that population was slaves or conquered peoples that could not qualify for the army. I'm not exactly certain whether or not they could have raised more if those slaves were free or if having slaves required more military presence by such a huge margin that it levels out or favours the army. Given how many slaves were in the city of Rome itself which wasn't defended by the legions directly it seems likely that full time military were not used to counter slave populations.

Those numbers may also fail to include the Vigiles which were the professional police of Rome.

By percent though, the Roman Empire had fewer men in the legions than they had during the height of the Republic. At the height of Roman military power in the Republic they managed over 700,000 legionaries with a population less than half that of the Empire. That was after the Marian reforms where a legionary was a professional soldier as compared to the Hastati civil soldier.

I've seen estimates that indicate Rome never had more than fifty million and estimates that at its height it had over a hundred. I'm not sure which is true. The Roman army could grow in size for specific campaigns, to be sure, so at any given time there may have been a greater percentage in military service. An army raised up by a politician for a specific war pre-Marian is by no means a standing army, and as far as I'm aware, even post Marian the army was typically a small percentage of the population. Also, the Marian Reforms ended up killing the Republic. I'm familiar with the 700,000 figure, but that was a brief period. A candle that flashes bright and burns out. It wasn't practical and ended up, (along with a few other factors,) resulting in the death of the Republic.

[Mendicant]

The highest I've ever seen for Rome was 60 million people living within their borders, only about 10 million of them living in Italy. Officially, the Roman Empire seems to have had about 450,000 troops. Given this was at a period of relative peace though, it seems likely that if an adversary arose at that time, the Romans could have raised more.

I'm also trying to figure what the percentage of that population was slaves or conquered peoples that could not qualify for the army. I'm not exactly certain whether or not they could have raised more if those slaves were free or if having slaves required more military presence by such a huge margin that it levels out or favours the army. Given how many slaves were in the city of Rome itself which wasn't defended by the legions directly it seems likely that full time military were not used to counter slave populations.

By percent though, the Roman Empire had fewer men in the legions than they had during the height of the Republic. At the height of Roman military power in the Republic they managed over 700,000 legionaries with a population less than half that of the Empire. That was after the Marian reforms where a legionary was a professional soldier as compared to the Hastati civil soldier.

450,000 legionaries was actually about peak strength for post-republican armies--the empire was always at war somewhere. That's maybe .7% of the population.

The Ming army, at its height was ~1 million, but 70 to 80% of its soldiers spent the vast majority of their time farming. If we put the active Ming army at 250,000, that gives us around .33% of the population. If their entire reserve army was pulled up, you'd crack 1 percent of the total population.

When the Mongol-founded Yuan dynasty wanted to invade Japan a second time, the Japanese mustered about 40,000 troops to oppose them, out of around 6.2 million people. That's around .65% of the population, which is in keeping with the trend we're seeing in the estimates of Roman and Ming troop strengths.

I'm sure there were reserves, private armed guards or retainers, and local militias, but 1% of the population under arms is just extremely uncommon prior to industrial-era warfare, but even in that context only immense wars like WWII actuall produce different numbers. If you look at the size of the US armed forces right now, active, guard and reserve, you're still looking at about .7% of the population.

Damn, this puts a spanner in my campaign works, if a town with 15,000 people in it is threatened by war by a nation with a 20,000 army you'd think they'd surrender right away.
Damn, I need to figure some things out then.

Mmm, not necessarily. There are a lot of other considerations. Remember, just because you have a total troop strength of 20,000, that doesn't mean you can actually employ them all in one place. If that state has opportunistic, powerful neighbors, or a noble class that isn't very reliable, it'd probably be pretty stupid to pull up every active soldier in order to conquer one city state. Moreover, they might not even be able to if they wanted to--mustering a feudal army was not an easy process, and you could generally only keep it under arms for a limited campaign.

A city-state is also unlikely to exist purely as a city--it'd also include a decent swathe of surrounding territory to draw defenders from. An independent city would also be a mercantile center of some kind, with more ready cash than its more agrarian opponent, making it much better at calling up mercenaries.

Historically, city states often produced higher-quality citizen militias than the imperial/royal levies they faced down, and combined with mercenaries, temporary alliances with similar city states, and the logistical advantage of fighting on your own turf regularly fended off opponents who were quite a bit more powerful on paper.

[Yukitsu]

450,000 legionaries was actually about peak strength for post-republican armies--the empire was always at war somewhere. That's maybe .7% of the population.

The Ming army, at its height was ~1 million, but 70 to 80% of its soldiers spent the vast majority of their time farming. If we put the active Ming army at 250,000, that gives us around .33% of the population. If their entire reserve army was pulled up, you'd crack 1 percent of the total population.

When the Mongol-founded Yuan dynasty wanted to invade Japan a second time, the Japanese mustered about 40,000 troops to oppose them, out of around 6.2 million people. That's around .65% of the population, which is in keeping with the trend we're seeing in the estimates of Roman and Ming troop strengths.

I'm sure there were reserves, private armed guards or retainers, and local militias, but 1% of the population under arms is just extremely uncommon prior to industrial-era warfare, but even in that context only immense wars like WWII actuall produce different numbers. If you look at the size of the US armed forces right now, active, guard and reserve, you're still looking at about .7% of the population.

Rome didn't fight major campaigns until they were divided though, at which point their percentage of soldiers in both East and West actually rose significantly. Pre-empire they were able to bring in huge numbers of troops to fight their major wars.

For the Ming it is almost certain that they had over a million men who were capable of fighting without additional training. It's harder to categorize these troops since they're more or less strategic reserve troops. In the event some hooligans or bandits ran into town however, it should be safe to assume that they are available as soldiers. In context, the OP isn't really asking about people who are actively under arms, but who could defend their village with some level of proficiency.

I've seen estimates that indicate Rome never had more than fifty million and estimates that at its height it had over a hundred. I'm not sure which is true. The Roman army could grow in size for specific campaigns, to be sure, so at any given time there may have been a greater percentage in military service. An army raised up by a politician for a specific war pre-Marian is by no means a standing army, and as far as I'm aware, even post Marian the army was typically a small percentage of the population. Also, the Marian Reforms ended up killing the Republic. I'm familiar with the 700,000 figure, but that was a brief period. A candle that flashes bright and burns out. It wasn't practical and ended up, (along with a few other factors,) resulting in the death of the Republic.

It's pretty hard to peg down any singular cause as the death of the Roman Republic or even if they were better off as a Republic rather than as an Empire. I would certainly see the constant use of the army under the later republic as something that allowed people like Caesar to ascend to the title of Emperor but at the same time I don't think that huge numbers of troops actually directly caused that, smaller armies could still have conquered Rome under a talented general who was willing to take that army across the Rubicon. The professional army rather than a citizen militia likely contributed more than the 700,000 professional soldiers did.

[Urpriest]

10-20 people who are armed and know how to fight, and another several hundred people with bows or boarspears who know how to hunt.

If it's an internal town, with only fields around in all directions, maybe not. But people who live in a frontier village know how to live on a frontier.

See, that's the thing. We probably should count people who regularly engage in paramilitary activities, like livestock rustling and poaching, in the settlement's military.