The fantasy genre is stuffed with sieges, even in series other than Lord of the Rings! From the Battle of Winterfell to whatever Prince Caspian was doing at Aslan’s How, fantasy storytellers are always eager to show us battles of catapults and scaling ladders.
But sieges are complicated, especially when you can’t just knock down the defender’s walls with a cannon. If you’ve ever read or watched a fantasy siege and been unsatisfied,* it’s likely that the writer didn’t have a sound understanding of how sieges actually work. To make sure that doesn’t happen in your stories, let’s give you a firm grounding in the subtle art of kicking someone out of their castle.
The War of Supply
It hardly takes a degree from Medieval U to know that sieges are all about supplies, but it’s not a simple matter of showing up and waiting for the defender’s food meter to hit zero. The contest over supplies is a huge part of siege warfare, so it’s important to understand in detail.
Stripping the Countryside
The first people to suffer in most sieges are not the attackers or defenders, but anyone who lives in the hinterlands around a besieged fortress. If a castle or walled city is too strong to directly attack, as they often are, the invading army might simply plunder the surrounding lands instead. They get a lot of free stuff, and they might even convince the defending garrison to come out and fight, lest their precious sheep crop be ruined forever!
If that doesn’t work, the attackers might simply withdraw and come back next year, confident in the knowledge that they’ve economically devastated their enemy without needing to fight a battle.
If that weren’t bad enough, the defenders also have an incentive to strip the countryside in preparation for a siege. Not only do they need to stockpile supplies for themselves, but they need to make sure there’s nothing for the attacking force to take. This applies to more than just food and water. If they can, many defending commanders will also see the area around their fortress cleared of timber and other building materials so the attackers can’t use them to make any pesky siege engines.
This will obviously make life hell for anyone who lives in the area, but hey, at least they can take refuge in the fortress, right?
Maybe not so much. The more people living within a castle or walled city, the faster its supplies will be used up. In purely military terms, a defending commander usually wants only the number of people needed to optimally defend the walls and not a single person more.
Ideally, non-combatants are evacuated to safety before a siege ever begins, but that’s not always possible. There might not be anywhere safe to send them, or the siege might come as a surprise. This can lead to a situation where those viewed as “unnecessary” are expelled from the walls and put at the attacker’s mercy. If the attacker isn’t willing to let these freshly minted refugees through, they might end up sandwiched between the two armies with nowhere to go.
Fortunately, this doesn’t necessarily have to happen, as it will depend on the defender’s mindset and objectives. If the commander sees themself as a protector of the people, then they probably won’t exile anyone to gain a tactical advantage. Or they might want to, but they find their cold calculus thwarted by a garrison that refuses to put civilians in harm’s way. It all depends on the situation you set up and how brutal you want this siege to be.
Outlasting the Besieger
While starving the defender out is a time-honored tactic in sieges, this isn’t a one-way street. In fact, the attacker is often at just as big a risk of running low on supplies. Sometimes, the attacker is even worse off. A castle or walled city may have huge stockpiles to draw on, whereas a besieging army is limited to whatever they can bring with them, especially if the defenders did a good job stripping all food from the surrounding countryside.
Attackers with good supply lines may be able to last indefinitely, but this isn’t always the case. Rough terrain and distance from the home country often make supplying an army difficult, to say nothing of enemy action. If the defender’s allies are still active behind the attacker, they can wreak havoc in the supply chain with a few well-placed raids. That’s actually why it’s so important for an army to take every fortress in its way: leaving an enemy garrison behind you is a good way to have your supply lines cut.
The approach of winter can also be a time limit for your attacker. The defender can sit nice and warm in their fortress, but the besieger will have to construct their own quarters from scratch or risk freezing to death. Very determined attackers might commit the resources to do this, which is how you get sieges that last years, but others will be forced to withdraw until spring.
Finally, defenders always have the hope that an allied army will arrive to relieve them. If such a force exists, then it will be a major problem for the besieger, as their worst case scenario is being pinned between the hammer of a relieving army and the anvil of a secure fortress.
Blockading the Besieged
Keeping the defenders from resupplying is a requirement for any siege, but it’s by no means guaranteed. The attacker must have a large enough force to encircle the besieged fortress, and even then, it’s possible to slip shipments through. Allies might try to sneak cartloads of food up to a castle’s walls by night. If so, the besieging force will attempt to seize the carts for themselves.
In general, the bigger a fortress is, the more soldiers an attacker will need to blockade it. An army of a few hundred could be enough to completely cut off a small fort, but the massive capital of a sprawling empire will require an army in the tens of thousands, at least.* Of course, a bigger fortress also takes more soldiers to properly defend, so it’s a tradeoff.
Clever attackers can make blockading easier by constructing fortifications of their own. If they have the material and engineering expertise, they might even build a wall that completely encircles the defending fortress, at which point anyone trying to sneak supplies in will have to get creative. Attackers who are really in it for the long haul might then go on to build a second encircling wall so they have something to hide behind in case a pesky relief army shows up. This can lead to absolutely wild sieges, where the attacker is besieged by allies of the fortress they’re besieging.
Starvation and Squalor
As exciting and cool as sieges are, there’s no getting around that being starved out is hell on the people who have to go through it. Going hungry is bad enough all on its own, but a reduced diet also weakens the immune system. Combine that with the overcrowding that’s common in a siege and you have the perfect recipe for outbreaks of disease. Scurvy is a particular problem during sieges, as foods rich in vitamin C often don’t store well, but that’s just the tip of the sickberg. Dysentery is another common siege-illness, and you can even bring in epic nasties like the bubonic plague if you’re feeling extra mean.
This isn’t just a problem for the defender either. Besieging armies also face the difficulties of malnutrition and illness. Often, the attacker might even have it worse since at least the defender has shelter already built. Meanwhile, soldiers outside the walls have to build their own quarters and sanitation systems. If those aren’t up to snuff, then disease will be even worse. No one likes living next to an overflowing cesspit, and not being able to get warm when you come back from patrol can also weaken the immune system.
All told, it’s not uncommon for more people to die of hunger, thirst, and disease than in the actual fighting. Disease is already a prodigious killer of humans, and putting a bunch of soldiers close together in hastily built siege lines only makes it worse. As conditions degrade, desertion also becomes a problem, especially for the attacker. It’s just easier to run away when there’s not an army blocking your path.
Defenses and Fortifications
There’s a reason pre-gunpowder sieges are so often decided by the war of supply. In the era before cannons, fortresses were the king of warfare, usually able to hold back any assault with ease. These defenses can get complicated fast, and understanding exactly how they work will have a big effect on how you portray sieges.
When you think of castle or city walls, you probably think of stone – and with good reason. Stone is famous for its lack of softness, and it’s relatively easy to stack up into nice, strong walls with just a little mortar.* You can go deeper into the details of masonry if you want, like how castle walls are often constructed of two solid slabs with a bunch of rubble piled in between, but that’s not usually necessary. Most of the time, all you need to know is that stone walls can easily be strong and tall enough to form a serious barrier.
But wait, not all walls will be built out of stone! Stone is expensive and takes a really long time to quarry and shape. Stone castles will take a minimum of several years to complete and be a serious burden on the pocket of even the wealthiest feudal lord.
When there isn’t the time or money to build fortifications from stone, wood is the next best thing. A wooden wall isn’t nearly as strong as its stone counterpart and is significantly more flammable, but that doesn’t mean it’s useless. While a simple wall of logs can be chopped through with an axe and a lot of determination, engineers can strengthen the wall by adding dirt. Just put up two wooden walls and then dump soil into the gap between. That way, when attackers chop through the first row of logs, they’re faced with a wall of dirt instead of new doorway.
Wooden fortifications are especially useful for besieging armies looking to strengthen their position, but defenders will use them too. Often, stone walls will be enhanced by adding extra wooden structures on top of them to provide better cover for the defenders. As a bonus, once the entire structure has been covered over with a finish of plaster or wattle and daub, stone and wood will look the same to any enemies.
A fortress isn’t doing its job if all it brings to the table is an obstacle for the enemy to climb over. Instead, every element of a fortress is designed to give defenders an edge in killing anyone with the poor sense to make an attack.
You can see this in the basic design of fortress walls. Crenellations are designed so that defenders have an easy place to lean out and shoot at the enemy.* Arrow slits provide even more protection, allowing archers to unleash volley after volley with almost no chance of being hit in return.
Fortifications are also designed to make the best use of their great height, with murder holes and machicolations for dumping all manner of unpleasant things on attacking troops. Boiling oil is the trope, but oil is expensive, so it’s more likely your defenders will use boiling water, superheated sand, or just regular chunks of stone. Don’t worry, those are all perfectly capable of inflicting horrific injuries.
Many fortresses are also built to limit the ways an attacker can approach them. The only approach to the gatehouse might be up a narrow switchback trail, or between two stone walls specifically built for the purpose. Either way, these narrow avenues bunch attacking soldiers close together so they can be cut down with arrows or crushed by falling boulders.
In a purely military structure like a castle, this design may continue to the interior rooms as well. Doorways will be made intentionally small so they can be easily blocked, and hallways will twist around in unpredictable paths to confuse anyone unfamiliar with it. Even the stairs can deter invaders: narrow stairwells that rotate clockwise mean an attacker climbing up has their weapon arm trapped on the inside,* while defenders can swing down with ease.
What, I ask you, is better than a wall? If you guessed “two walls,” then congratulations – you have a future in the exciting field of fortress construction. When time and resources allow, it’s always better to construct extra layers of defense, as each new layer makes the fortress that much harder to take. After all the work of taking one wall, the attacker can only weep in frustration as the defender retreats to a second wall and starts the process all over again.
In the basic castle design, there’s one outer wall, and then an inner keep that represents the second line of defense. Fortified cities will often have an outer wall and then an entire castle inside it as a backup. But it’s also fairly common for castles to have a second, third, or even fourth set of walls. This doesn’t happen as often for city walls, since there’s a lot more ground to cover, but it’s not unheard of. Historically, Constantinople’s Theodosian Walls were constructed in two layers, making the city all but impregnable for centuries.
Another major advantage to layered defenses is that the second layer can support the first. In most cases, a second wall will be higher than the first, and the third higher than the second. This means that missile troops on the inner walls can fire on attackers as they climb the outer wall. It also means that if the besieger actually manages to take a wall, they’ll be totally exposed to attack from the next layer of defenses.
Moats are a really important aspect of defensive engineering, but they’re also poorly understood. Despite what some of our childhood stories might tell us, moats are almost never filled with water, at least not on purpose. And they certainly aren’t filled with dangerous animals. Not only are those expensive to feed, but they’re notoriously bad at following orders.
Instead, a moat is essentially a large ditch, usually dug in front of a castle wall, and they serve two important purposes. First, they break up any assault before it reaches the wall. Charging soldiers first have to climb down into the ditch, and then climb back up out of it, all while carrying their scaling equipment. Moats are even more effective at stopping siege towers, battering rams, and anything else that has to be moved on wheels.
Second, a moat makes tunneling beneath the walls much more difficult. Any tunnel that aims to get past the moat will have to go that much deeper, and if the moat goes down to the bedrock, then tunneling might simply be impossible.
Sieges are primarily defined by a small force holding off a more powerful one by the virtue of walls and other defenses, but that’s not the entire story. In most cases, the defending garrison isn’t actually trapped inside their walls, and can emerge to attack whenever they like. They probably can’t defeat the attacker in open battle, this wouldn’t be a siege if they could, but fast raids are another matter entirely.
One obvious target for sorties is the attacker’s store of supplies. If the defender can put their besieger’s food to the torch, or even carry it back into the fortress, that can easily swing the tide of battle. It’s also possible for the defenders to go after isolated pockets of their enemy, picking off the attacking army piece by piece. This is especially likely if the attacker has had to spread their force out to form a blockade, and it’s one reason that the besieger is likely to build fortifications of their own.
To make sorties harder to predict, most fortresses will have multiple entrances. That way, the enemy can’t just camp their entire force outside the main gate and feel safe. The downside is that more ways out also means more ways in. So-called sally ports are usually well defended, but having more of them is still a calculated risk.
Taking the Walls
Few commanders ever want to attack an enemy fortress, especially without the aid of gunpowder. And yet, sometimes these attacks are necessary. The attacker may not have enough food to outlast their enemy or a relief force may be on the march. Either way, a direct assault with ladders and grappling hooks is almost guaranteed to fail unless the attacker has truly overwhelming numbers. Even then, they’ll probably lose so many soldiers as to make any victory Pyrrhic at best. Fortunately, the defender isn’t the only one with a few tricks up their sleeve.
Just because there’s no gunpowder, that doesn’t mean you can’t have machines that hurl heavy objects at people you don’t like. These weapons generally rely on storing energy in twisted rope or animal sinew and then using it to impart energy on a projectile via a throwing arm or sling. In modern parlance, such artillery is usually referred to collectively as a catapult, even though this category includes a diverse range of weapons like onagers, mangonels, and scorpions.
One thing all these weapons have in common is that they are not particularly useful against stone walls. The projectiles they can throw just aren’t heavy enough to cause real damage. Instead, they’re typically used to destroy wooden fortification or aimed at the defenders themselves. That way, the defenders are more likely to keep their heads down during an assault.
There is one major exception: the counterweight trebuchet. Based on historical records and modern recreations, it is possible to build these massive weapons big enough to destroy even the mightiest castle wall. However, that doesn’t mean they’ll be common. For one thing, these things are really hard to build, requiring a lot of material and engineering expertise. For another, they have to be built on-site, within range of the enemy walls, because they’re really hard to move once in place. And if the trebuchet is in range of the walls, that means it’s also in range of the defender’s return fire. Traditional catapults might not be much use against stone walls, but the defenders can absolutely use them to smash a trebuchet to bits.
At its most basic, a battering ram is just something heavy used to break through obstacles. Simple versions will be a rough log carried by a team of soldiers, but this has limited power and the soldiers themselves are completely exposed to whatever the defenders rain down on them.
More complex rams resemble a sort of shed on wheels. The roof provides protection, and the ram itself is suspended by ropes so it can be swung back and forth for additional power. Particularly advanced models might even include fortifications on the roof where archers can provide covering fire.
In fiction, we typically see battering rams used against a castle’s gates, and while that’s a valid way to employ them, it’s not the only way. Rams can also be used against the walls themselves. This may not work on the stoutest stone fortresses, but it’s perfectly valid against weaker targets, especially wooden walls.
The main weakness of rams is that they have to get all the way up to the wall to be effective. This is especially difficult for the wheeled variety, as they can get stuck in mud, moats, rocky ground, and anything else that makes it harder to keep a heavy cart rolling. Plus, being at the wall’s base means you’re in a perfect position for the defender to drop something heavy and/or flammable on you.
Towering above the battlefield and rolling forward on enormous wheels, siege towers are perhaps the most intimidating weapon in the pre-gunpowder arsenal. Like trebuchets, they require a lot of material and skilled engineers to build. It’s also very difficult to move them any great distance, so attackers will usually have to construct them once the siege has already started. Even so, siege towers are almost certain to make an appearance in any major siege, as some fortresses are just impossible to take without them.
Siege towers are probably most famous for rolling up to a wall and discharging a squad of attacking soldiers, and they can certainly be used for that. However, conveying troops isn’t the siege tower’s only purpose. They’re also really useful as elevated shooting platforms. As long as the tower is built higher than the wall, attackers can use it to shoot down on the defenders with bows and small artillery. This forces the defenders to stay behind cover, making it possible for assaulting troops to begin their climb.
For all their power, siege towers also have a lot of vulnerabilities. For one, they’re made of wood, which is notoriously flammable. Engineers will try to make their towers fire resistant by covering the outside with wet cloth, animal skins, and even seaweed, but there are no guarantees. Siege towers also make perfect targets for any artillery the defender has lying around.
But by far the biggest problem with siege towers is their mobility, or lack thereof. These towers are incredibly heavy, and require teams of soldiers or animals to move, even on level ground. If you thought battering rams were likely to get stuck in the mud, you weren’t thinking big enough. Often, preparing a path for the siege tower is as big a job as constructing it in the first place.
If artillery, battering rams, and siege towers all sound a little too complicated, then can I interest you in an enormous pile of dirt? That’s what we in the biz refer to as a “siege ramp,” which is a very useful tool for any besieging army. The idea is to pile soil and debris at the base of a wall until you have an incline gentle enough for soldiers to walk up so they can go and introduce themselves to the defenders. If you’re feeling fancy, you can sink support timbers into the dirt to make it more stable, or lay down gravel, stones and plaster to create a smooth road up to the top. That allows you to bring a battering ram up to attack the wall at a higher and therefore thinner point, or you can even wheel an entire siege tower up the ramp.
While siege ramps are pretty simple from an engineering perspective, they require a lot of labor to build, because of the sheer volume of material involved. That’s why you’re most likely to see them at sieges of large cities or truly enormous castles. In a smaller siege, the attacker just doesn’t have enough soldiers to build something like this.
The construction also requires the builders to get progressively closer to the enemy walls, which will attract swarms of arrows. The attacker can always use siege towers to provide covering fire, but there’s a simpler solution: build the ramp from inside an armored shed. Laborers would construct these sheds from well outside arrow range, then move them into place and start work. When they were finished on a section of the ramp, they’d move the shed forward and start again. For larger ramps, sometimes a line of these sheds would be used so workers could more easily bring tools and building materials where needed.
When faced with a siege ramp, defenders would naturally try to pick off as many of the workers as possible, but this wasn’t likely to succeed unless they had the firepower to break through the protective sheds. Alternatively, the defenders might try building their own walls higher, though this new construction was likely a lot weaker than what it was built upon. Finally, the defenders might even try tunneling under the ramp and taking dirt out from its middle. This sounds like something from Looney Tunes, but it’s a great way to keep the ramp from getting any higher.
Tunneling is one of the most effective options available to besiegers, but also the most dangerous. Tunneling takes a long time, but it’s a much surer way to bring down a defender’s walls than anything else a pre-gunpowder army can muster. The operation is simple in theory: specialized soldiers called sappers would dig a tunnel until they reached a point under the enemy walls, then they dug out a large chamber supported by wooden beams. Once finished, the sappers set the supports on fire and ran. The chamber would collapse, creating a sinkhole and hopefully bringing down a section of wall above.
In practice, sappers have a high chance of dying on the job, assuming the local ground is suitable for tunneling at all. Cave-ins can be common, making experienced sappers hard to come by. Suffocation is also a serious risk, as the tunnel might break into a pocket of asphyxiating or poisonous gas. And for all that, the tunnel could end up completely off target, or it might not be big enough to undermine the walls.
For all those problems, tunneling is still extremely effective, and any competent defenders will prepare for it. One way to detect tunneling is to put bowls of water out on the ground and watch for any ripples caused by vibrations in the earth. The defenders might also just put their ears to the ground and listen for the sound of tools. Once the defenders know that a tunnel is incoming, they would probably dig their own tunnel to intercept it. This could lead to underground battles as both sides try to collapse the other’s excavation. Historically, these battles sometimes became pretty elaborate, and there’s even an account of one garrison releasing bears into an attacking tunnel during a Roman siege, if you like your fantasy warfare on the cartoonish side.
Assuming the tunneling succeeds, it’s not an automatic game over for the defenders. They might have lost a section of wall, but now there’s an enormous rubble pile that the attackers have to get over. That’s easier than climbing an intact wall, but it’s still no picnic.
It’s also possible to tunnel all the way into an enemy fortress and get soldiers inside the walls that way. However, this is even more difficult than undermining the walls, as it requires a tunnel that can stand a sizable force walking through it. Worse, these subterranean soldiers will be at a major disadvantage as they emerge from a confined space right into the defenders’ spear points, so being spotted can doom this type of attack before it starts.
The Effect of Terrain
Supplies, walls, and artillery are all important siege, but there’s another factor that humans* have far less control over: terrain. Terrain plays a major role in all forms of warfare, but it’s even more influential in sieges because the two sides are no longer on even footing. Certain terrain favors the attacker, while other kinds favor the defender. Understanding this difference is crucial to properly depicting a siege.
This is an attacker’s dream. There’s plenty of room to maneuver, and the path to the walls is clear and flat. Plus, plains might mean fields and farms that the besieger can plunder for supplies. In fact, flat ground is so disadvantageous for defense that few leaders will build fortresses there if given a choice. Of course, sometimes the choice is made for them by strategic or economic interests.
The main danger for attackers on an open plain is if that plain happens to be a desert. In that case, the besieger has little chance of getting food or water from the countryside and will have to depend even more on their supply lines. Flat plains are also noticeably short on trees, denying the attacker the lumber to easily build siege engines.
Temperate forests are also relatively favorable terrain for the attacker’s purposes. They’re not as open as a flat plain, but all those trees mean a constant supply of siege material, not to mention fuel to burn in the winter. This is a serious problem for the defender, so much that a defending garrison will go to extreme lengths to clear any trees from the lands surrounding their fortress.
Forests also provide the attacker with decent foraging opportunities, something else a defender isn’t going to be happy about. This isn’t likely enough to supply a large army, but it can supplement whatever edibles the attackers brought with them.
There are few things defenders like more than having part of their fortress protected by water. It’s a tad difficult to march soldiers or wheel siege towers over water, which severely limits the attackers’ options. They can build boats of course, but that’s a good way to get sunk or set on fire. This is such a big deal that when possible, military engineers will often dredge artificial lakes to protect their castles.
The more surrounded a fortress is by water, the harder it is to attack. This makes islands the dream location for any castle designer, though islands have limited space. When there’s no land approach, attackers have to get creative, which might include mounting artillery or battering rams on their ships and trying to batter down the walls that way. Or they might go full Alexander the Great and just dump dirt into the water until they have a land route after all.*
If a fortress is located on open water like the ocean or a large lake, then the defenders have yet another advantage: they can be resupplied by boat. This means the attackers will need a navy of their own to complete the blockade and can lead to some exciting sea battles.
Swamps and Rocky Ground
The immediate effect of rocky ground on a siege is that tunneling is much more difficult and sometimes impossible. The uneven terrain can also make it harder to move siege engines around, which is a major boon for the defender. Swamps do essentially the same thing, only to a much greater degree.
In a swamp, tunneling is essentially impossible because the ground floods as quickly as workers can dig it out. Any attacker hoping to undermine the enemy walls would first have to drain all the water, and that’s difficult even with modern technology. Then there’s the mud, which will suck up heavy artillery and siege towers like they’re going out of style. Moving anything heavy across a swamp requires a lot of effort to put down a serviceable road first, and any such construction isn’t likely to last long.
Swamps also make the already high risk of disease even worse. High humidity levels spoil food, and biting insects spread viruses all around the besieging camp. Equipment degrades faster, and morale takes a serious hit. None of this is fun for the defender either, but at least they have a pre-built shelter. Granted, building a fortress in a swamp is no easy feat.
Mountains and Hills
The main effect of walls and towers is to create an artificial high ground, so you can imagine how important natural high ground is in a siege. The higher up a fortress is, the harder it is to assault. The attacker has to haul not only their soldiers but all their artillery and equipment up the slope, and then still deal with the defender’s walls. Not a great situation.
The only drawback is that more elevated fortresses are often harder to supply since the number of routes up to them is limited. This can hamper any relief force, but it’s usually a small price to pay for hindering the attacker’s trebuchets and siege towers.
If there’s high ground available that isn’t already claimed by the defender, the attacker had better snap it up quick. Positioning their artillery on a hill or ridge can allow the attacker to rain stones down inside the fortress, which is a major nuisance when you’re trying to make the castle presentable for the king’s visit.
Trickery and Negotiation
Until now, we’ve looked primarily at the ways attackers and defenders can gain an advantage in a siege. Those are certainly important, but they aren’t the only factors at play. Even a successful siege is costly and time consuming, so the commanders in your setting will try to avoid one if at all possible.
The first option is through trickery and guile. In this approach, the attacker tries to end the siege by sneaking in through an unsecured window, bribing a guard to open the gates, or even dressing their own soldiers like the defender’s reinforcements and getting them inside that way. You’d be amazed how many historical sieges ended this way, from Belisarius sneaking into Naples through a randomly discovered pipe to Sultan Baibars capturing the Krak des Chevaliers via a forged surrender document. It’s difficult to say what tricks the characters in your story might use, but remember that they’ll always be on the lookout for the opportunity.
The second option is negotiation, which is a huge part of siege warfare. In short, the attackers don’t want to spend the lives and resources necessary to either assault a fortress or starve it into submission, and the defenders don’t want to still be around when their walls finally fall or their food runs out. If the defenders’ prospects look hopeless, they have a strong incentive to negotiate, and the attacker has a strong incentive to accept. This is how you end up with the defending garrison marching away without a fight, or at least with less of a fight than there might have been.
Naturally, a lot of factors go into these negotiations. If the defending commander has a particularly strong position, they might be able to arrange for every soldier and civilian in the castle to go free, with whatever wealth and weapons they can carry. More likely, the negotiation will result in the defenders going free with no weapons and just enough food to reach the next town. If the defenders’ position is especially bad, then being taken prisoner rather than being executed might be the best they can hope for.
Such negotiations are never conducted with perfect knowledge, and sometimes a particularly brutal attacker will refuse to accept a surrender because they want the glory of storming the walls. Dedicated defenders might choose to fight even when it’s clear they can’t hold out, especially if they have a cause they believe in. However, these situations are likely to be the exception. Sieges are a particularly costly type of warfare, and most rational people will avoid one if it’s a viable option.
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