[Worldbuilding] Modelling places which are built on completely different assumptions?

This leads me to ask how you intended the “Climate” factor on the "Environmental Adjustments to Demand table to be interpreted. (And I apologize for taking this thread off topic, but the Forums won’t let me post new topics anymore).

I have assumed that the Climate categories represented a combination of two factors: temperature (Cold, Temperate, or Hot), and dominant vegetation (Trees, Shrubs, Grass, or Barren). So we get:
Cold + Trees = Taiga
Cold + Shrubs = Tundra
Cold + Grass = Steppe
Cold + Barren = Polar [Doesn’t appear.]
Temperate + Trees = Deciduous Forest
Temperate + Shrubs = Scrub
Temperate + Grass = Grasslands
Temperate + Barren = Barrens [Appears in Wandering Monster section.]
Hot + Trees = Rainforest
Hot + Shrubs = ? [Doesn’t appear.]
Hot + Grass = Savanna
Hot + Barren = Desert

But, judging from you analysis above, it looks like you were going for something more like how climates/biomes/whatever are actually classified, and then cramming them into a gameable number of categories. Which means that savanna should apply to places with mixed grass and trees, regardless of temperature, and both the Pacific Northwest and the Amazon should be classified as rainforest. Is that more like what you were going for?


Well, it's not necessarily wise to make rowers and marines the same thing; you want your rowers fresh for rowing, and you don't want your marines exhausted by rowing before they even set foot on an enemy deck. Thus many ships of the era distinguished quite clearly between the two, though sometimes rowers could be co-opted as light infantry either in desparate circumstances (the ship has been boarded!) or for raiding.

Rowing is also a particular skillset that doesn't automatically translate to being good for fighting. There was usually a small complement of archers and another of marines on board a galley.

If I’m not mistaken, the main advantage of a galley was speed. Except perhaps under miraculously favorable wind conditions, a ship under oar will outpace a similarly sized sailing ship by a huge margin. Speed was important to military vessels in antiquity not only for maneuvering, but also for ramming, which was more or less the go-to tactic in ship-to-ship engagements until well into the Roman period.

Taking that into consideration, I suspect that the switch from galleys to sailing ships for trade had a lot to do with how safe the sea lanes were for merchants. If you’ve got the might of the Roman or Athenian fleet to keep pirates at bay, sailing ships make a lot of economic sense. On the other hand, a sailing vessel in more dangerous waters would be a sitting duck, particularly before the development of the lateen sail (another Roman period innovation).

Actually I think the reason that galleys remained the preeminent military vessel for so long as their maneuverability and reliability compared to sailing vessels. A sailing ship could outrun a fully manned galley if it had the wind with it, and it could definitely outpace a galley from a strategic perspective, couple that with the fact that they were far cheaper to operate because they required a significantly smaller crew and that made them ideal for trading, but they fact that they were so dependent on weather made them unsuitable for naval combat tactics of the time. It would have been extremely difficult to ram an opposing vessel with a sailing ship. It wasn’t until the maturity of gunpowder, when loading a ship with cannons along the broadside rather than rowers made it more powerful in combat, along with the development of more sophisticated sailing rigs that allowed for more fine control of ships,even sailing against the wind, and galleys were finally made obsolete right around the end of the 16th century.

What I’ve been reading about the history of ships mostly agrees with what you’re saying, but I’m not sure you’re right about sailing ships being able to outpace a fully manned galley. I believe that most galleys were equipped with sails as well so that they could continue to move under sail when the rowers needed to rest. Furthermore, before the development of the lateen sail, sailing ships were unable to tack very close to an oncoming wind, meaning that they were vulnerable not only to being becalmed, but also to days when the wind just wasn’t blowing their way.

Going by Wikipedia, it looks like a 5th century BCE war galley probably had a cruising speed of 7-8 knots, and could reach a speed of up to 10 knots for short sprints. The same ship under sail was capable of an estimated top speed of around 8-9 knots in fair conditions, though I don’t know how fast a differently designed sailing ship of the day might have been able to go.

Galleys, of course, were vulnerable to poor weather as well, and couldn’t maneuver under oar in rough seas. Under such circumstances I would guess that a dedicated sailing vessel would be at an advantage in terms of speed, though I don’t know how big the advantage would be. I’m admittedly only guessing, but based on the general fickleness of weather, I suspect that galleys and sailing vessels would be pretty comparable in terms of speed on a strategic scale.

Since originally answering this post, I have expanded and deepened the mathematical models I originally built for ACKS. This has led to some more richness in my understanding of city economics.

  1. Above I wrote “the total economic activity in a town attributable to its population* is roughly 10 times the maximum amounts listed on the Markets & Merchandise table.” In fact, it is roughly 36 times the maximum amounts.

  2. Here are the approximate number of merchant ships that a typical city of minimum size for each category could support per month:
    Class I: 30 Large Ships, 90 Small Ships, or 45 30-horse Caravans
    Class II: 7-8 Large Ships, 22 Small Ships, or 11 30-horse Caravans
    Class III: 3-4 Large Ships, 11 Small Ships, or 6 30-horse Caravans
    Class IV: 1 Large Ship, 3 Small Ships, or 2 20-horse Caravans
    Class V: 1 Small Ship or 2 10-horse Caravans
    Class VI: 1 10-horse Caravan

  3. The profit that can be earned from monopolizing arbitrage, passenger, and shipping within a city is approximately 15% more than the profit that an independent city of the same size generates for its ruler. See “Merchant Ships and Caravans” table for the profit per ship/caravan.

EXAMPLE: the mercantile profit from a Class I city (20,000 families and 30 Large Sailing Ships) would be (30 large ships x $2591 per ship) 77,730gp per month. The rulership profit from the same city, if independent, would be (3.34 x 20,000) 66,800gp per month. Note that 66,800 x 1.15 = 76,820. [Why 3.34? 3.34 = 8.5gp base - 2gp garrisons - 1.5gp upkeep - 1.66gp festivals]

So if you want to create an independent city-state like Venice where the rulers are merchant princes, you can increase their monthly profits by up to 115% to reflect their mercantile holdings.

You could also divide the mercantile holdings between multiple families, if desired.

Any thoughts on “garrisons” that are actually the ability to muster the population as militia, rather than a standing force? I treated them as 1/4 the regular cost, which seemed to produce the right sort of figures.

In the periods of antiquity I’m dealing with, a garrison was something a foreign power (or local tyrant) imposed on a city to keep it in line, not a welcome source of law and order.

Great question!

Do you happen to know what level of taxation the citizens of a Hellenistic city-state faced? I wonder if - since the citizens themselves were the army - the citizenry paid lower taxes to the government than a city of Imperial Rome paid to Rome for the Roman legions.

If so, you might simply treat it as a wash - the city-state doesn’t have to pay its garrison cost (2gp per family) but it collects 2gp less in urban income per family. And the city-state is assumed to be able to call on a military force with monthly wages of (2gp x # of families) as needed.

For a city of 50,000 people (10,000 families) that would mean 20,000 gp per month - enough to field 1,500 heavy infantry.

In Athens, at least, they paid taxes as well as being expected to train and muster*. In the fourth century BC there were 30,000 adult males in Attica paying about 6,000 talents a year in tax. I’m assuming that’s silver, not gold.

Although later payment of taxes became an excuse not to train and muster (as also happened in later Principate Rome), with the expectation the state would hire mercenaries/pay the landless poor to do the fighting.

*And the poorest citizens were expected to train as rowers, though this was unique, most other city-states used professional (non-citizen/foreign) oarsmen.

A silver talent is equal to 6,000 drachma, which in ACKS terms, are worth 1sp each. So 1 talent = 6,000 sp = 600gp.

6,000 talents x 600gp = 3,600,000gp per year.
3,600,000gp per year / 12 months per year = 300,000 gp per month
300,000 gp / 30,000 families = 10gp per month

Average tax/fees per peasant family in ACKS = 12gp per month
Average garrison per family in ACKS = 2gp per month
12-2gp = 10gp per month


Ha, funny that it turned out that way. The bulk of it was actually paid by the top 10-20% of those 30,000, but that’s already built into the maths as I remember.

In the case of Athens (the place we have lots of evidence for, not the norm by any means) there wasn’t a single source of taxation, but lots of them (over a hundred). Along with voluntary liturgies to pay for all sorts of things, taking them on carried great prestige showing what a good civic supporter you were.

If I attempted to model the distribution of wealth and the varieties of taxation in more detail than I have already done, I am fairly certain even the ACKS community would abandon me. Hehe.

I really enjoy the fractal nature of ACKs, where there are detailed models hiding underneath relatively simple numbers. In that way, you can delve down into more complex iterations of a particular system, or you can simple trust the average result as long as that’s good enough. Building castles in the core rules vs. in D@W is a fine example of this. I think the fact that the differences in garrisons and taxations just coincidentally does a good job of approximating a real-world city with a unique situation is amazing!