Why would civilizations with advanced technology still use castles?

Question

Despite being awesome marvels and once incredibly important, ever since explosives became a thing, castles have become obsolete. Until now...

Imagine two equally advanced civilizations at war. Both factions feel as if castles make great forts in that day of age (futuristic scifi).

These castles externally appear as if they are medieval castles but are also armed with higher degrees of defense mechanisms such as force fields and anti-aircraft turrets. They use the castles to hold weaponry and supplies, house troops, and to hold strategic defensive locations.

The civilizations don't use exclusively castles but I would say that about 33% of each faction's forts are castles.

Why would civilizations with advanced technology (think Star Wars-like technology) even consider using castles as forts?

Answer 1

Advanced civilizations would find something like a castle useful for the same reasons that civilizations have always found fortresses and castles of various types useful; Because the combination of materials technology and defensive architecture available at that time can overcome the ability of weapons to deal damage to a protected target.

If we think about a future civilization with FTL technology (you mentioned "star wars"), we can easily postulate that they would have developed some extraordinary materials technology in order to have an FTL ship that could withstand the stresses and impacts it is likely to see during normal operation.

Development of some material strong enough to handle the abuse that FTL travel would probably dish out would radically alter the offensive/defensive paradigm. We could assume that if a ship can be built out of Superstuff, then why not a fortress?

We would have to figure that the combination of architecture and materials would be enough to resist/defeat a nuclear strike AND orbital bombardment with something like "god rods". That means we are talking about materials so strong that even if the part of the planet underneath the fortress were vaporized by an asteroid, it would largely be intact. That means the fortress would have most of the characteristics of an FTL ship but probably just lack the drive itself.

This could be something that they find useful because of the expense of the drives and the value of whatever other resources are on the planets. We can compare this to the way that castles served as a point from which small armies could "sortie" out against an enemy. Even if the rest of the planet is vulnerable to orbital bombardment, the fortress would be able to cause a lot of damage to attackers while they were within close enough range to attack.

Strategically, this might look like the Napoleonic naval war era, where ships were basically floating artillery platforms, but they always had to worry about the superior guns that could be placed on an enemy fort, and forts were built to cover the entrances of strategically important harbors.

Answer 2

It's not the technology level which makes castles valuable or worthless, it's the differential between the value of being able to hold still, defending a spot of land, and the ability of the attacker to bring offensive weaponry to bear against said emplacement.

Castles were very effective in their era because the kings of the day could afford to spend an inordinate amount of labor building structures that were virtually impenetrable to any weapon of the day. The invention of siege weapons changed the balance a bit, but it was still plausible to build a castle so strong that no siege weapon could take it down. This balance was destroyed with the invention of the cannon. No stone structure could withstand the beating that a cannon unleashed on it.

The key to this is the sense of time. A king could spend decades building his castle and strengthening it against attackers. Attackers, limited by the mobility of offensive weapons at the time, were unable to keep up. There was also a strong sense of desire to stay in one place. A king did not want to move from his castle, so once it was up, the king could just stay there.

So those are the keys to having scifi castles:

• A reason for powerful people to want to stay in one place for a long period of time.
• The ability to shrug off any siege weaponry which could be brought to bear.

The latter is the one which is hardest. Modern combat has found many ways to deal with a foe that is willing to hunker down like this. We're so good at destroying things these days, that the most effective combatants are those which are always on the move. That way you can never bring to bear our particularly powerful weapons on them. However, if your technology is shifted such that this is no longer the case, castles could become a thing again.

Answer 3

Some thoughts:

1. The materials used to construct the buildings could be comparably advanced and resistant to the weapons of the period.

2. Similarly, there could be some inherent trait about their weapons technology that makes a certain natural mineral or material resistant to it, so that material is used in their constructions.

3. There could be symbolic reasons for wanting to have your bases appear certain ways. For instance, perhaps there's a cultural motivation to invoke some historical location or imagery.

4. Depending on the exact nature of their approach to warfare it may actually be advantageous to have a structure like a castle for defense. For example if conflicts largely revolve around ground-based attacks and foot soldiers, it might make a lot of practical sense. Or maybe battles take place entirely in caves. Or perhaps something in the atmosphere hinders their ability for aerial-based combat. Etc.

Answer 4

Castles, like any fortification, are designed to project power over an area and at the same time resist being taken over. What makes a castle different from a "base" or "bunker" or other fortification is crenelations, arrow slits, moats, double gated archways. These are all things designed to protect counterattackers and make it really hard for ground-based troops to enter.

You said these castles have force-fields and anti-air defenses (anti-ship, missile, energy beam, god-rod, etc.). Well, once it's clear that air assault will not work, an attacking commander may well switch to ground-assault.

It may be that force fields can deflect an energy beam, but maybe they can't stop a physical slow moving object (like a foot-soldier). So, perhaps high-tech weapons have cancelled each other out enough that old-school D-Day style frontal assault is the only choice.

And what would be really handy when you've got thousands of armed troops running at you? Crenelations, arrow slits, moats, and gates.

In reality, though, I would think a CIWS would take care of just about anyone coming at you. And those things are scary automated. So, to be fair I guess the foot-soldiers would have to have some pretty good armor. Totally doable.

Answer 5

They don't have gunpowder.

In an Alternate History Hub video about gunpowder, or the lack there of, he points out that without gunpowder for bombs and cannons, walls around a city is still a good strategy.

You can still have your world have advanced knowledge of chemistry, physics, medicine and mathematics. The can have democracies and vehicles, but without gunpowder to make things go boom, walled cities (basically a large castle) are still a great defensive strategy.

Answer 6

Logistics considerations. "Castles" are built over strategic-critical resource deposits, which removes the overhead of maintaining resource extraction lines.

A sci-fi castle might also be mobile (put a set of massive engines on the bottom so it can relocate). Maybe envision something like the Command Center building in StarCraft, except that it can land on resource nodes and harvest them. Throw in a ring of surface-to-air missile batteries (the "Detector" type, to break enemy stealth) and artillery cannons (probably ripped from decommissioned siege tanks) - that will make it difficult to attack from both ground and air.

Answer 7

Privacy

Your faction's troops are well armed and well trained. But when the enemy snaps a photo of their faces, their AI goes to work. Perhaps they posted something "embarrassing" to social media, or stupidly picked their nose in an apartment bedroom "guaranteed" to be free of terahertz spying devices. Now their families are being targeted for humiliation. If that doesn't work, their families can always be targeted for assassination. The troops, of course, try to be masked and anonymous like Mexican drug police, but when the enemy is willing to use high intensity X-ray beams to sow cancer worries, this can only go so far. The troops tend to stay pinned down in some safe spot, hopefully out of sight, so that they do all these things to the enemy with fewer distractions. A castle, by any other name.

Answer 8

For some reason, certain stone materials are the only substance that can penetrate force fields

Say you were able to develop a force field dome, the kind of device that you lay on the ground, and which projects a beam into the air, which then arcs down, producing a near-impenetrable hemispheric energy phenomenon that stops all but the strongest projectile, explosive, and directed energy weapons. A device say, that could even provide a degree of protection against strikes from our contemporary nuclear bombs.

This essentially resets you back to the pre-gunpowder era. Attackers can try to chuck stuff at your defences, but you as the defender have the huge advantage. You have two weaknesses, one old, one new. The old weakness is you can't easily resupply yourself, which allows your enemy to besiege you until you have no choice but to surrender. The new weakness is that your force field dome is just as impenetrable from the inside as it is from the outside, so you have no means whatsoever of counterattacking your enemy.

So let's handwave that there actually is a way to make little windows in your dome, and that is via some particular quality of the sort of blocks of stone that just so happened to be the kind of material that medieval people built their castles out of. So your fortification will be as follows:

• In the centre, the force field generator
• Surrounding the generator, all the various buildings and facilities needed to maintain your garrison.
• Right at the edge of the force field, stone walls, with protrusions pressing out into the force field, disrupting its effect just enough to create a small window through which a weapon can be pointed out.

The outside view of this fortification would be a stone structure, with tiered walls, stepping back in keeping with the invisible arc of the force field dome, dotted with crenel windows near the top of each wall level, through which a futuristic energy weapon peaks out.