Creating a system of warfare for dispersed port cities

[Yora]

I created a setting inspired by ancient Greece, in which pretty much all civilization takes the form of coastal city states that are separated from each other by vast stretches of almost impenetrable forest. There are effectively no land borders and no way to capture valuable mines without conquering the whole city state first. To protect against raids, most treasure and grain is stored inside the royal palace behind the city walls.

I was wondering how warfare would look like in such a world? Traditional land wars seem out of the question. You can only transport and supply your army by sea.
You can go and raid another city state, but you would not have much chance to assault the city walls and there would not be much loot on the outside. Trying a siege would be very hard because of the trouble of bringing in supplies for your army. You could destroy crops and then try to come back after the next winter and try a siege when their food is low, but your army wouldn't last long either.

The only really practical way I see to attack an enemy city is to attack its merchant ships at sea. Drain them of resources that way. But that's probably not going to be terribly reliable as you have to find and catch a good portion of them to make a serious dent.
If your merchant ships keep getting attacked, then sending out your warships to chase the enemy's warships sounds even more challenging. But in that case you might have a good chance to make a surprise raid against the enemy harbor and try to steal or destroy as many ships as possible. The ships are the one thing they can't get safely inside the city walls.

So as I am seeing it right now, the name of the game would be commerce raiding and attacking fleets in port.
And I have to admit I am not seeing much reason for war in this setting other than fighting for control over sea trade.

Could it be that by creating a forest dominated world, I also created a naval warfare setting? Not that I would object to that.

[Max_Killjoy]

With very little opportunity to march armies overland...

There will be a lot more spying, intrigue, influence efforts, etc. Damaging enemy cities with internal strife, supporting coups by factions more sympathetic to your interests, developing fifth columns to seize and neutralize defenses at critical moments of your assault, etc.

[InvisibleBison]

Trying a siege would be very hard because of the trouble of bringing in supplies for your army.

Why do you think this would be the case? As I understand it, it's generally easier to move goods by water than by land. And while in theory the enemy navy could attack your supply convoys, on the one hand you'd have to have already more or less eliminated the enemy navy in order to safely bring your army to the enemy city to besiege it in the first place, and on the other hand the possibility of raids on supply lines has not historically prevented sieges from happening.

[Mechalich]

Presumably your city states are surrounded, in the immediate sense, by concentrated farmland. So you pile your troops into ships, sail (or row) over to the neighboring city, disembark a mile or so down the coast, and then besiege from there by building a temporary wooden fortification in the middle of your enemy's prime farmland. The key difference is in the matter of resupply, rather than controlling the overland supply routes the besiegers need to control the sea routes to prevent resupply, but there are numerous historical examples that serve as a model - the various sieges of Constantinople for instance.

[Ninjadeadbeard]

I think naval combat is going to become the predominant form of open warfare. But as Max_Killjoy said, espionage and intelligence will become a major force. I think also, this sort of warfare will lead to something more akin to a typically Shadowrun/Cyberpunk style of Big Government structure becoming popular. Highly complex, structured, and powerful central governments will be required to engage in war over such distances and with the supply issue being as it is. War might take a long time, and have very few actual sieges (blockades though), but it will be organized.

I'd also note that if Magic can whip up any real sort of power in the setting, every side is going to be using it to maximize one of their advantages. Or, in the event that someone strong/desperate enough shows up, someone might start looking at Magic as a sort of Weapon of Mass Destruction. Why blockade the city for a decade when I can flood it with water elementals? Or turn everyone in it to stone? Or simply vanish them into another dimension? Lots of possibilities. It can get downright Tippyverse if teleportation becomes a thing.

[Xuc Xac]

The first question I would want answered is "Why are they fighting at all?"

"We're starving because we don't have enough food. How do we get more resources?"
"Let's go attack that city that isn't bothering anyone. They must have all the food they need in their city."
"But they're well fed and prepared while we're half starved. There's no way we can take them."

[Yanagi]

I created a setting inspired by ancient Greece, in which pretty much all civilization takes the form of coastal city states that are separated from each other by vast stretches of almost impenetrable forest. There are effectively no land borders and no way to capture valuable mines without conquering the whole city state first. To protect against raids, most treasure and grain is stored inside the royal palace behind the city walls.

I was wondering how warfare would look like in such a world? Traditional land wars seem out of the question. You can only transport and supply your army by sea.
You can go and raid another city state, but you would not have much chance to assault the city walls and there would not be much loot on the outside. Trying a siege would be very hard because of the trouble of bringing in supplies for your army. You could destroy crops and then try to come back after the next winter and try a siege when their food is low, but your army wouldn't last long either.

The only really practical way I see to attack an enemy city is to attack its merchant ships at sea. Drain them of resources that way. But that's probably not going to be terribly reliable as you have to find and catch a good portion of them to make a serious dent.
If your merchant ships keep getting attacked, then sending out your warships to chase the enemy's warships sounds even more challenging. But in that case you might have a good chance to make a surprise raid against the enemy harbor and try to steal or destroy as many ships as possible. The ships are the one thing they can't get safely inside the city walls.

So as I am seeing it right now, the name of the game would be commerce raiding and attacking fleets in port.
And I have to admit I am not seeing much reason for war in this setting other than fighting for control over sea trade.

Could it be that by creating a forest dominated world, I also created a naval warfare setting? Not that I would object to that.

Do the island nations have a shared culture of warfare?

Because one way out of the strategic bind of total war is for them all to accept a kind of bounded conflict that everyone understands the "rules" to rather than have every fight fall into a free-for-all. For example, duels between champions, fights between small units until one flees or is incapacitated, ransoming captives rather than outright killing, full combat but with certain fixed rules about engagement (such as infantry meeting in a flat, open field).

Presumably there are trade pressures because resources are not equal, so they'll be haves and have-nots, and periodically those tensions will get big enough that outright conflict happens. A lot of "war" of whatever variety would start with a "poor" city-state attempting to fill a deficit in its pile of resources: pasture and/or arable land, valuable raw materials, fresh water, currency-equivalent trade goods, manpower. But there would also be wars where a wealthy city-state decided to establish permanent control over a weaker city-state rather than have a trade exchange, or where two wealthy city-states competed over monopolization of the trades of various third-party city-states.

There'd be states built on the premise of piracy--theft from ships--and raiding--theft from countryside adjacent to waterways, sustaining themselves entirely on re-circulating stolen goods through trade systems. These entities would essentially always be a state of low-key warfare with other city-states, but try to avoid sustained conflict with anyone. Depending on the demand for hard labor and skilled labor, piracy would include slaving and holding key individuals for ransom. Depending on the distribution of technological know-how and raw materials, ships themselves could be assets.

And I think it's worth mentioning deliberate wrecking as a kind of "tactic" that would be easier in a D&D style fantasy world--with weather magic and undersea beasties capable of making sinister deals--such that a desperate community or city state could prey on other navies while maintaining a slender but firm layer of deniability.

Privateering--state-endorsed piracy versus targeted competitors--and
chevauchee--raiding to destroy the productivity of land--apply the same tactics to a different long-term objective--extracting concessions and tribute rather than just seizing goods.

The efficacy of siege would come down to questions of logistics outside the parameters provided: how much suffering the besieged can afford versus how effective the besiegers can sustain themselves at distance via naval supply chain, which should be different for every city-state and every island. However, the possibility of siege and naval movement of land troops would lead to the seizing and fortification of positions of logistical importance--critical high-traffic waterways, un-colonized islands with strategic significance (such as a fresh water supply, or a critical position)--as defense-in-depth of the city-state proper. Boom chains at key positions could be as important as castles, and defended as aggressively. This in turn means that there could be on-land combat to hold strategic positions to allow safe and efficient movement of one's naval forces--the equivalent of the Siege of Malta, or the Dardanelles campaign.

Controlling seaways from fixed positions is another place where magic and the supernatural are an added wrinkle...effectively bring an "ancient" world to parity with modern developments like fortified artificial islands. Intelligent use of a "wall of" spell, summoned beings, altering currents or creating whirlpools by creating ice or stone that changes water flow...the permutations of how to "control" a waterway extends beyond this-world methods.

Other posters have mentioned espionage, but I think it's worth elaborating that idea to include sabotage--specifically arson--assassination, terror, and other unconventional warfare. Island city states with a small number of central depots for vital war material, with limited pasture/arable land, with limited timber for ships, and with a few critical industries, are especially vulnerable to attacks on war infrastructure. Such acts could be performed wholly in secret, undermining a target long-term and making them pliable in the faces of demands or concessions, or within a short time frame to make them vulnerable to invasion. Fire...magical or just old-fashioned pitch and oil...would be incredibly powerful as a way to weaken an opponent clandestinely or create an opening for an outright invasion.

And I would argue that, yes, invasions and sieges would occur. First, because the creation of a permanent trade imbalance sustained by threat of force--colonialism--at some point becomes an option when a state has enough wealth and military power, and is exercised because the status quo and standard of living has to be maintained with cheap(er) labor and raw materials. Secondly, within the flow of goods and services that make up trade, there come bottlenecks in which a few critical resources are so valuable that it makes sense to expend blood and treasure to have direct control and thus dictate the market. Third, there comes a point where population exceeds the combined sustenance available through agriculture and trade, and expansion...either seizing existing arable land through war or creating pioneer settlements to create new farmland...is necessary. Fourth, the pivotal resources of a city-state society can experience both critical-time-frame failure--drought, blight--and permanent failure--exhaustion of a mine, a mass-casualty event--resulting an a state of crisis where military aggression seems like a viable option for the sake of survival (or, at least, the survival of a comfortable status quo).

[Yora]

Lots of good point to consider.

To make sense of tactics, there first needs to be a strategy (which general throughout history still surprisingly often failed to consider). And to create strategy, you first need to know what the goals are. "To win the war" is a very bad reason to start a war.

My idea is that every city state is able to supply itself with food and construction material most of the time, but they all rely in some way or another on a trade network for metal, salt, silver, medicine, and luxury items like wine and silk. However, natural disasters are a constant fear of all the cities and destruction of crops a permanent threat. When that happens they would have to import food, and generally the other cities don't have much to spare.

So the two main reason for conflict that I am seeing are control of trade and secured access to specific resources, and famine. The goal of war is to change where goods and money go, and in rarer cases to quickly grab a lot of food.

I think I have to read up on the politics of the Delian League/Athenian Empire. I think they consisted mostly of small island city states that were all dominated by Athens, and the Athenians were really not known for their soldiers. Somehow they managed to do that only with their navy.

[Eldan]

Are your cities monarchies? I could perhaps imagine hostage taking and ransom as a way to do this. Send a team of "heroes" to kidnap an other city's favoured princess, then demand half their food stores in payment.

[Yora]

Not sure anyone would pay that high a price, but hostages and ransom seem like great elements to add into the mix.

[sktarq]

Two of the other reasons I could see war occurring is face/honor and internal reasons.

You have described cities as being significantly large and complex with presumably multiple power groups supporting the "royal" or local equivalent. This opens the possibility for coups, civil wars, etc. Which also raises the question of why is the king (chancellor, cardinal, grand high archmagus whatever) the leader? Presumably they draw on a source of support and power in both practical (direct command of the army, direct control of the food) and social (think the Chinese mandate of Heaven, the Egyptian Ma'at, the weddings of Ishtar in Mesopotamia) ways.
All this means that internal rivals may provide reasons to go to war that don't make sense "logically" from the entire city-state's perspective.

Rival Princes looking to establish backing with various groups by handing out booty from raids or status in in the kind of grand raids where major cities are hit (see how the Persians raided Antioch for example) A "raid" that broke a city that is not long term controllable but looted that "royal palace" holding the food/trade goods etc would provide a LOT of booty and status for the commander to buy support with back home.
Also cities may have competition and rivalries where if their rival goes out and has a successful raid/conquest etc. Others feel driven to match it as to not loose their perceived status (and quite possible very real influence and advantages) either internally or with third parties. A city that is known for being capable in sieges battles etc is one that may well having greater leverage during trade negotiations etc as the local leaders fear them walking away and coming back to just take what they want, and that reputation may be worth fighting for)
Or allying with a particular group (noble family, military, ship building guild specializing in military ships, aggressive church) for reasons of internal benefit may seem to be reasonable to weak leaders but they end up being pushed into war even if it is not in the city's best interest as a whole in order to keep his ally happy.
Also if a leader is weak or facing internal divisions sending out a war fleet (options include getting rid of trouble by sending it away, or getting everyone on the same team, to show strength and leadership in order to gain acceptance or acquiescence by other internal groups) could be another reason. For example a city that has suffered raids and whose leader is fearfull that they may be replaced and that other cities may see his city as weak and unable to protect themselves may feel inclined to go to war to gain the confidence of his internal subleaders (reestablishing his right and status to lead in battle etc) as well as causing other city states to be wary of facing their warriors.

Basically reasons internal to the individual city state can drive intracity behavior that is otherwise not logical or missing

[Yora]

I can see civil wars with foreign support working quite well. The king can hole up inside the city, but when the invaders have team up with noble estates outside the city, they together have the means to take control of the farms, mines, and other resources.
Then the king would be forced to march out to end the revolt quickly or the ursupers will be running the country.

Interesting scenario.

I'm not planning on making war a serious part of the campaign, but it will be good to have some ideas how war could look like when it happens.

[Yanagi]

I think I have to read up on the politics of the Delian League/Athenian Empire. I think they consisted mostly of small island city states that were all dominated by Athens, and the Athenians were really not known for their soldiers. Somehow they managed to do that only with their navy.

The Delian League started as a defense pact against probes by the Persian Empire, but slowly transitioned to an Athenian Empire because the latter had the most leverage--in the form of ships--and began demanding and getting concessions from the weak states that couldn't stand against the muster of Athens and whatever league members backed Athens. This in turn led to the Sicilian Expedition and the Peloponnesian War. If you're so inclined, Thucydides' work on the subject is an amazing piece of history.

(There's an old BBC version that breaks down "The Peloponnesian War" into a series of dialogues and has actors recite the exchange of messages and arguments between city-states. It's on Youtube, chopped to bits, if you want a sampling.)

Also worth looking at would the history of the Barbary Corsairs, who were alternately full pirates and mercenaries for the Ottoman Empire; the Phoenicians who dominated the naval trade until the Greeks came along--including being a mercenary navy for anyone who could afford it (including the Persians); and the history of Venice as backstabbing skullduggery trade master that situated itself between the Ottomans and Europe to dominate the subcontinental spice trade.

There's also the story of the Sea Peoples...sometimes characterized as an invasion...in which a natural disaster prompts a mass migration, resulting in massive societal upset for the whole Mediterranean. And in the same vein there's the Thera eruption that ended the Minoan civilization and (probably) created the Atlantis myth.

And while I know less about it, it would probably be worth looking up the history of Indian Ocean-side trade--specifically the history of Yemen, Oman, and Zanzibar; trans-Saharan trade routes (where its deserts and oases rather than salt sea and islands) that went through places like Jidah (Mecca) and Petra; and the trans-Asian Spice Road and Silk Road routes that elevated cities like Kabul, Bukhara, and Yerevan as trade nexuses. Maritime portage as an economic niche and caravans as an economic nice employ similar strategies, and desert cultures caught up in the latter might provide slightly out-of-the-box ideas for what a magical Mediterranean setup could look like.

My idea is that every city state is able to supply itself with food and construction material most of the time, but they all rely in some way or another on a trade network for metal, salt, silver, medicine, and luxury items like wine and silk. However, natural disasters are a constant fear of all the cities and destruction of crops a permanent threat. When that happens they would have to import food, and generally the other cities don't have much to spare.

So the two main reason for conflict that I am seeing are control of trade and secured access to specific resources, and famine. The goal of war is to change where goods and money go, and in rarer cases to quickly grab a lot of food.

It occurs to me that feuding and civil war would be an omnipresent threat for city-states, and that between the sea and the forests there would be whole regions--for example, sprays of small islands or patches of land scattered up the side of mountains--that would constantly experience small-scale conflict because of relative privation and isolation from authority. Sort of like what you see in Sicily, the Hindu Kush, or Appalachia...constant skirmishing rooted in land usage and familial alliances. This would be the backdrop against which city-states politics would form...either as a monarchy coagulates or mutual-aid agreements create a limited-franchise democracy...and the political primal mud into which failed city-states would subside.

You're describing a setting with city-states on basically the same level in terms of basic needs, but have hit the transition point where the surplus value from subsistence (farming, foraging, herding) can just maintain a concentrated population of non-subsistence workers and experts, such that city-state governance can operate. To avoid relapse or collapse, pressure to expand...increasing that surplus value...would be enormous, and have consequences for warfare. If every city state is straddling the same tight margin of food versus population, disputes over critical resources are going to get very ugly very fast*. If state-level action to maintain a surplus fails, collapse and internal conflict will follow. In the short term looting and food riots--but also factionalization related to holding and harvesting land in the long term.

_{*Barring some kind of agreed-upon limited warfare to act as conflict resolution. The Iliad includes descriptions that suggest that the early Greeks had exactly that kind of system in place...with hero duels and combat outside the walls rather than a true siege. I don't have a sense of scale on your setting, but if your region is comparatively small and the cultures emanate from a similar belief or value systems, or if each state is heavily interdependent on the others, the more likely there'd be some kind of agreed-upon format for warfare over specific claims...but also that this would break down in times of great urgency or high stakes.}

As such city-states would likely have to engage in another kind of internal warfare in which state actors define borders not through maps, but by enforcing their hegemony over outlier communities that could trade independently: intervening in feuds and stomping on bad actors that revert to banditry and range war. The tighter the overall subsistence economy is--because there is a bullet-meets-the-bone point where trade goods can only buy food that exists--the more strategic each and every calorie source is.

The absolute bottom of this kind of collapse is migration in force...what the Sea Peoples were doing, and what motivated at least some of the great steppe tribe invasions...so there's a point where internal problems translate into external military issues.

How pressure to subsist expresses itself in inter-state warfare depends on how tight the system-wide deficit-or-surplus problem is.

If there's relative (regional) privation but an overall surplus in the market, you're going to see raiding, piracy, and wrecking as short-term tactics to acquire exchange goods or currency to buy sustenance. Sort of like how hill and steppe folk become bandits in times of hardship, or how maritime people resort to piracy during crisis, such as the Ryukuans and the wokou near Japan, of the Orang Laut near the Straits of Malacca. If there's a lot of surplus value moving around in trade, but relatively little privation, full-time pirate states like the Barbary States are a viable tactic to become wealthy...though this requires a marketplace of divided, complicit trading partners unwilling to unify against a rogue actor...and even to create a rump empire operated like a protection racket. That last bit being what went sour with the Delian League. Athens transitioned from "this is mutual defense" to "this is you paying us to defend you...or else."

The ubiquity of pressures that generate raiding dovetails pretty well with the likelihood in this setting of selling military labor as a wealth-creation strategy. Since armed forces logistics are expensive even beyond the expense of maintaining a city, all trained soldiers--because the city state has to have some soldiery--can become assets rather than expenses if they're shunted into an existing conflict as mercenaries. And if you're a city state with no notable hard assets--no critical resources (like tin, or copper), no finished goods deemed high-value (pottery, wine), or valuable rarities (like saffron or silk)--sending folks off to war for wages is a good gamble. This can be seen in Xenophon's Anabasis, where hoplites participate in a Persian succession conflict, in the Phoenicians selling their services to the Persians as trireme pilots and combatants, and in the Italian city-states usage of (infamously unreliable) condotierri.

Any time there's a shoving match between your city states, there's going to be hungry--literally or figuratively--third parties willing to supply bodies and ships. This can both be played straight--hiring forces to stand under a banner--or in varying shades of skullduggery, such as pirates acting as proxies damaging the readiness of an opposing state through raids. It can also diminish the overall escalation of warfare, if mercenaries are unwilling to lose customers or really put themselves on the line--as tended to happen in Italy--but it can also escalate the situation if the mercenaries are completely disengaged from the conflict's regional stakes and only in it for pay and pillage rights.

Sidebar:

Impenetrable forests create...interesting...implications, depending on how literally "impenetrable" they are. Clearing forest to create agriculture-ready land...or simply land that provides better foraging outcomes...is near-universal, and requires little more than fire and the most basic stone and wood tools. Even if the an area can't be totally transformed into fields, it can still be exploited for swidden agriculture, altered with selective burns to create an environment more hospitable to edible plants and animals (as Australian and American natives have done).

Barring supernatural levels of difficulty, the forests are going to have people in them. People are just terrifyingly durable and very clever at coming up with strategies to avoid danger, evade disease, and hit that necessary calorie-per day number. The Amazon has a lot of people in it; archaeology suggests it had many more before European diseases swept through. There would likely also be cultures that specifically develop in the marginal region between the forest and the "livable" territory with mixed forage and horticulture strategies--rather like what the Eastern American tribes who created Cahokia managed. Indeed, there would be locations where the intersection of forage conditions, fresh water, and marginal land would create non-maritime cities...the equivalent of the ones found found in the Central American interior.

But to maritime city states nearby forests represent a development opportunity, and the more desperate the subsistence economy is, the more likely someone's going to try development even if it has hazards. There's a cost-benefit analysis that's going to happen about the worth of new pasture or new fields, or the worth of a road...and somebody's going to be desperate or crazy enough to bite.

So far the operational premise has been that states care about the populace because their people are valuable to the economy of the state and thus the health of the state. Even if everyone is not equal under law, all have utility value such that it's better they're not dead. But there's also a viable economic strategy where you just take people--usually from other places--and try and extract labor from them, and the "success" condition is if they create value relative to the expense of their capture and maintenance before they drop dead. Given the kinds of pressures on each city state, there's going to be someone that's losing the trade game...no goods, no strategic position from which to act as a hub and levy fees or tariffs...but is sufficiently militarily strong to consider slave colonies as a mixed economic-military strategy. Capture land, disperse or kill population beyond what you can control through force, transfer surplus that would otherwise sustain local development back to your own city-state is a viable strategy: it's what kept the Spartans operational.

But when you add in the forest, there's an ugly bit of added value: if you develop the forest using expendable enslaved labor you "win" by acquiring the land that fed another city state; "win" again by extracting labor from a controlled populace that does not get a share of the surplus or to participate in the trade economy--meaning more growth and better quality of life for your own people; and "win" yet again in that the surplus people might contribute some labor before expiring; and you lose nothing if they run away or die in the forest.

In effect, the forest becomes the equivalent of the Caribbean and/or the Belgian Congo: a viable strategy to succeed if you devalue life enough.

[Yora]

The main fantastic element of the setting is that nature spirits are very powerful, the climate highly volatile, and the forest growing back very quickly and full of very large predators and unfriendly spirits.

Agriculture is only possible in places where the dominant spirit of the land agrees to protect people from all these dangers and create for them patches where fields can be kept clear and won't suffer from regular floodings and draughts, and the field workers won't be getting eaten by predators.
This effectively makes all these areas isolated islands and expansion into the wild forest isn't possible. Since building roads is also out of the question, any newly provided places for safe settlement have to be on the coast or new settlers can't get to them. And given their limited size, city states are the only viable form of government.
There are barbarians in the wilderness, but they also have their arrangements with spirits of the land that form a very complicated patchwork of places where they are allowed to hunt relatively safely, and tabu areas where the spirits don't tollerate intruders.

While there is a lot of unsettled land, the supernatural conditions make it unaccessible, so I think for practical reasons the city states can be thought of as being on small islands. The biggest one having 400,000 people, but many being only in the low tens of thousands.
I want it to be somewhat based on Bronze Age palace economies, but I admit that I don't understand it very well (and I believe historians don't either). The lesser nobles I put on Roman villas that manage the fields outside the city.
Since I don't know much about Bronze Age Greek kingship, but have seen the concept of basileus in the Trojan War interpreted as really more like a chief, I am helping myself out by drawing on Germanic kingship. So basically the king is an elected leader from among the noble patriarchs. Though that system was very decentralized without a fixed capital, so the Archaic Greek system must have been quite different.

But it seems that in the Greek world "city states" were often rather small fortified towns that had allegiance to a dominant city but were governed very autonomously, and switched sides pretty often. There seems to be almost no territorial cohesion among the states of the Delian League.
When we take the minor states into account, they could be where the major powers fight their wars. Smaller fortified towns could probably be taken by assault, or you could get control of them by supporting a coup without having to go through a full invasion.
A reason to switch allegiances would be to gain access to a different trade network that gets you much better prices on certain goods they have monopolies on.

I actually had planned to give the role of thieves' guilds to smugglers. Who wouldn't just be individual merchants hiding goods from customs, but big organized networks including corrupt court officials having permanent arrangements with foreign city states.

I also think mercenaries make perfect sense in such a setting. The noble estates would have their own armed and trained men and they all band together to form the army of their city state in war (which we seem to see in the Trojan War). That number is quite fixed and limited, and it makes much more sense to boost them with experienced mercenaries when needed instead of trying to maintain a conscript army ready at all times.

[Mechalich]

This effectively makes all these areas isolated islands and expansion into the wild forest isn't possible.

Given this, would it perhaps make sense to model your warfare based off a system that was island based. Looking from this perspective I think your best comparable might actually be Maritime Southeast Asia. That was divided into coastal city states that traded and fought primarily in the maritime environment because there was limited fertile land surrounded by largely impassable (and with the technology they possessed largely impossible to clear) jungle. The few inland settlements were mostly along rivers, as seen here.

Unfortunately, knowledge of how warfare in these societies functioned seems to be somewhat limited, because the relevant cultures were not literary and primary sources are limited mostly to what was recorded by outside observers. For example, Zhou Daguan's report on the army of the Khmer Empire in the late 13th century reads as follows: "The soldiers, too, go naked and barefoot. In their right hand they carry a lance, and in their left hand a shield. They have nothing that could be called bows and arrows, trebuchets, body armor, helmets, or the like. I have heard reports that when the Siamese attacked, all the ordinary people were ordered out to do battle, often with no good strategy or preparation." (Zhou, Daguan. A Record of Cambodia: The Land and Its People). Accounts do establish that people living in these states conducted raids for plunder, critically including slaves, which represented a key resource.

[Yora]

There are many stories of great ancient wars in Southeast Asia, but I was never able to find anything on how they actually fought.

[sktarq]

In which case you one option you want to look further south and east into Polynesia.

I would look at places like Tonga, Marquesas, and the Hawaiian island.

Eventually these places each basically unified but they went through periods where different islands or valleys (esp Tonga) were at war with each other.

Otherwise I would think that you may want to look at deep desert trading empires as well where camels substitute as the ships of the desert in terms of long range trade and war, how city-states can turn to trading empires (and thus what to avoid if you don't want that), limited expansion opportunities and the like.


also a question does come up with the supernatural spirit focused forests in this....how do the spirits of the sea factor into this because that could have a massive change in how warfare is conducted.
if the sea spirits basically don't care about humans then no real change but if they do then spirit talking becomes a major warfare and trade factor.

another question this spirit system would provide for conflict would be forage only resources conflicts.
if a resource is place limited (say a single island) and the local spirit will not allow people to settle then the only way to get that resource is to basically show up, gather, and get out. Especially if the island spirit is also responsible for the resource itself being non transportable (as in the key plant or animal won't grow off the island or it is a result of how the spirit reacts with the earth and produces special gems, clay, self heating stones or whatever) And some spirits may be faster than others to react so it may not be TOO dangerous if you are fast enough (though still good low level adventure fodder)....but because no one can settle there it becomes something that nobody can quite own but a bunch of groups will want access to and thus a source of conflict. So questions of zones of influence come up, negotiated shared access (and third party raiding or cheating leading to conflict), etc. and these fights could be rather different in nature as they may not be directed at the offending city state itself but well could be in a retaliatory way. Either way it opens up both a new source and style of conflict.

EDIT
another thing to think about....where is everyone getting the large amounts of lumber, pitch, and hemp/other fiber (ropes and sails) for these navies when they have such limited land that would have a high pressure to focus on foodstuffs.
I'm not sure what you would want here because big navies are very land intensive (especially as the fiber would have to be cultivated) and how many ships a given amount of land can support would be a significant factor in how both trade networks and warfare is conducted (how valuable ships are vastly changes how much risk people are willing to use them with)

[Hugh Mann]

I am going to be making a few assumptions here, but it could be possible to start a forest fire and have it spread to a nearby city.

Theoretically a group of arsonists could take a ship a few miles away from a city, wait until the supernatural weather starts a drought, then check the wind patterns. They could then just start a big fire that will blow towards the city, wrecking most of it's defenses and leaving it open to invasion.

This does assume that the nature spirits wont stop the fire, and that the arsonists can get upwind of the city without getting killed, and that the city isnt walled from all sides with a nonflammable material, and that the invaders are willing to sacrifice the crops, and that the city itself is close to the treeline.

Otherwise it is a pretty easy way to destroy a city's defenses as a raging forest fire can spread very easily. It could even destroy a city's docks potentually crippling it.

And supposing that this form of strategy works then many cities would take precautions like digging fire trenches. Although, due to the nature of this setting, information would travel slowly so not every city would know this.

[Ninjadeadbeard]

Just gonna throw this out there but Yanagi is really on point. I think you should look up the economic/trade system that supported the Near-East Bronze Age. Lots of city-states whose economies were interconnected with (even reliant upon) each other. War is ceremonial, or at least more about bragging rights than actually slaying your foes (since you gotta trade with them later). And if one city or resource is too disrupted by conflict, the entire system collapses and we get a Dark Age.

Extra History does a pretty decent analysis of the Bronze Age Collapse if you're short on time.

[russdm]

I created a setting inspired by ancient Greece, in which pretty much all civilization takes the form of coastal city states that are separated from each other by vast stretches of almost impenetrable forest. There are effectively no land borders and no way to capture valuable mines without conquering the whole city state first. To protect against raids, most treasure and grain is stored inside the royal palace behind the city walls.

I was wondering how warfare would look like in such a world? Traditional land wars seem out of the question. You can only transport and supply your army by sea.
You can go and raid another city state, but you would not have much chance to assault the city walls and there would not be much loot on the outside. Trying a siege would be very hard because of the trouble of bringing in supplies for your army. You could destroy crops and then try to come back after the next winter and try a siege when their food is low, but your army wouldn't last long either.

The main fantastic element of the setting is that nature spirits are very powerful, the climate highly volatile, and the forest growing back very quickly and full of very large predators and unfriendly spirits.

Agriculture is only possible in places where the dominant spirit of the land agrees to protect people from all these dangers and create for them patches where fields can be kept clear and won't suffer from regular floodings and draughts, and the field workers won't be getting eaten by predators.
This effectively makes all these areas isolated islands and expansion into the wild forest isn't possible. Since building roads is also out of the question, any newly provided places for safe settlement have to be on the coast or new settlers can't get to them. And given their limited size, city states are the only viable form of government.
There are barbarians in the wilderness, but they also have their arrangements with spirits of the land that form a very complicated patchwork of places where they are allowed to hunt relatively safely, and tabu areas where the spirits don't tollerate intruders.

While there is a lot of unsettled land, the supernatural conditions make it unaccessible, so I think for practical reasons the city states can be thought of as being on small islands. The biggest one having 400,000 people, but many being only in the low tens of thousands.
I want it to be somewhat based on Bronze Age palace economies, but I admit that I don't understand it very well (and I believe historians don't either). The lesser nobles I put on Roman villas that manage the fields outside the city.

I also think mercenaries make perfect sense in such a setting. The noble estates would have their own armed and trained men and they all band together to form the army of their city state in war (which we seem to see in the Trojan War). That number is quite fixed and limited, and it makes much more sense to boost them with experienced mercenaries when needed instead of trying to maintain a conscript army ready at all times.

I would say that based on your points, that the setting is not sustainable enough. The coastal city states may exist, but any real warfare would cause the entire system to just collapse. Nor would they still been in Bronze Age system, longer than a few generations. In reality, its falling back to either a stone age or copper age system; if not having the whole population die off.

1) Material problems

Bronze is not a naturally occurring element but is in fact an alloy of Copper and another metal/metals. That means any bronze goods require a supply of copper. Once the copper supply runs out, then that ends the bronze availability. Without a copper source, the people will fall back on stone tools.

Wood for ships and buildings, will be another major issue in the sheer power that you have given to Nature Spirits and Nature problems. Harvesting trees enough to make ships would become an actual issue, since it doesn't seem like destroyed or damaged ships can be repaired. Given how important the sea is, and how much everyday activities is tied to it, none of the coastal cities are going to be able to sustain their sea fleets for long. That removes merchant ships carrying goods to say nothing of warships. How are the city states getting enough wood to replace those boats of theirs?

Farmland will be limited due to your Nature Spirits, and so sea farming would become very important. There will need to be decent sized fishing fleets, or a number of fishing boats. This ties to the problem of wood, which would be needed for fishing boats, plus material to make fish nets or the like to harvest sufficient sea life.

Buildings, what are those made off? Is wood the primary building material? How does the populace obtain this resource?

2) Warfare

Based on your points, I would say warfare would be not possible, and at most there might be small raids. I don't see it possible for any kind of piracy to develop either. How are the troops acquiring any gear or weapons to use? Those who have to be made.

Where or how are pirates getting outfitted? How are they getting more pirates? Who are they raiding and for how long? After a certain number of pirate attacks, given the imposed limitations, none of the city states will trading with the others. Too many pirate attacks will make the merchants not willing to risk their goods.

Mercenaries need to be fed, and that food has to be produced somehow. Otherwise, they become less effective.

3) Water supplies

All of the coastal cities will need a supply of water unless they can drink saltwater. Presuming, there is no areas to get water that can drunk, then the cities will disappear. If they can get water, those locations will be heavily guarded and protected.

4) Supply replenishment

How is the materials dug in the mines and harvested getting replenished? How is the material being used to make bronze goods? How is the farmland getting replenished so that it can grow crops each year? A patch of land that is farmed repeatedly, especially given the imposed limits is going to go fallow a lot faster than if the locals could expand their farmland and give the used land a chance to rest.

5) Waste Disposal

How are the cities disposing of their produced waste? Where do they dump it? How do they handle it. They will need to figure that out.

Based on these problems, i can give you coastal cities bunch about maybe a few decades tops before it completely collapses, to say nothing of starvation or disease. In the confined area, you will see far more diseases and plagues happening.

[noob]

flood the entire sea with ships and naval platforms(possibly close enough for people to be able to send messages from ship to ship and contact the entire fleet(you could use sign tower(or whatever was the name of towers that could be used to send signals with movements(in france they started a network of those towers before they got telegraph but it is not tech that would look too anachronistic in a medieval setting)) tech on boats)) until your swarm of stuff reach the other country.
Since anyway plants are magically super good at growing you could even probably cultivate stuff on naval platforms provided you can get materials from underwater (like having a system that can recover materials at the bottom of the sea so if the water is not too deep it is possible) or you go full caster spam and use stuff like create food for supply issues(and also extensively encourage magical formations and faith and tell people that having everyone becoming a caster or supplying casting resources is the best thing to do).
Or it is just an epically hard logistics problem to get the resources to the right places.
A thing is that either overfishing is impossible or the big naval predators starts starving and then have to fight the boats and possibly a good civilization will have the means to beat the big naval predators(like adventurer strike teams or massive amounts of poison on each boat or any mean they could use to kill the predators) which afterwards makes the seas safe and from there civilization can start destroying forests(they just have to find how to cultivate while on sea)
With more numbers and more tech or communication you can solve more problems except for entropy.

[Clockwork333]

Are any of the city states technologically or magically developed enough to have hot air balloons or the like? I imagine air travel would be a game changer, though it seems your setting might be set a bit 'early' for that to come into play unless it's one particular city-state with a genius inventor's niche.

Are all of the city states human or are there other races like orcs or dwarves or whatnot mixed in?

Are the nature spirits pretty content to remain in their areas or does the forest fluctuate over time? Are there any other spirits in the world? Like comparable spirits in the ocean?

[Thinker]

Hi Yora,
I have been following your setting development off and on for a while. I'm not sure where you are currently, but here is my understanding:

• There are a few city-based polities that are powerful enough to field fleets, have impressive defenses, and are major players in the international trade network
  
  • Defenses might include land walls, sea walls, gates, watchtowers, guards, militia, and friendly nature spirits
  • These city-states have nearby fields, mines, and other resources that are harvested to benefit the elites who live in the city
  • These city-states rely on the trade-network for other goods (for example, City A might have tin while City B has copper)
  • These city-states may have other communities/tributaries that are within their sphere of influence that are not as strong as they are
  
  
• Tributaries
  
  • Primarily small agricultural communities who are not strong or wealthy enough to build a city
  • Defended primarily by militia and friendly spirits
  • Do not command fleets, but do participate in trade
  • Pay some portion to a larger nearby city-state for protection and insurance against being raided by that city
  
  
• Tribal/nomadic communities
  
  • Primarily hunter/gatherer or herd-based communities who do not desire to build a city
  • Little in the way of farmed or mined resources, but may have access to other resources - skins, bones, ivory, medicine, etc.
  • May have arrangements with spirits
  
  
• Sea-based communities
  
  • Primarily live off of trade and piracy
  • How welcome they are is based on their relations with individual communities

Assuming the above is true, you could have all kinds of warfare. The tribal/nomadic communities would be the most likely to raid the settled communities, assuming there is some path to reach them through the forest. You might also have the lesser communities (without the impressive walls and such) participating in raids on one another - even neighboring farms might be trying to steal cattle, like the Irish Cattle Raids.

Cattle raids might also be an inspiration for a concept of "raiding season". Early spring, after the last snowfall, it might be agreed that is raiding season where the different communities will raid each other. While violent, it might not often lead to many fatalities - doubling as sport as much as profit.

Also, keep in mind, that in a bronze-age agricultural setting, a community cannot afford to have many people who are not doing farm-work or fishing-work. Additionally, defenses are only as strong as those who man them. Having a wall won't stop raiders unless there are people on-watch to sound the alarm and fend off the attack. That suggests that light attacks and raids might be effective.

Another time for attacks would be after a disaster, when all-hands are needed to restore stability. Disasters cascade - a city-state that suffers an earthquake might be opened up to attacks from rivals and opportunists.

Large-scale war would have to be over important resources - tin mines, copper mines, gold mines, honor, etc.