Apocalypse. Nuclear war. Destruction. Human extinction. Well almost. A few thousands have survived, residing in a small town they have built from scratch, salvaging whatever they can.

Human progress has taken quite a hit. With no technology to help them and no one to recreate the technology, humans have regressed to a medieval way of life. No electricity, no internet, no democracy. The survivors are basically small bands of humans living together to protect themselves against the unnamed mutant horrors.

In this scenario, how feasible is it that -

  1. Humans have lost the ability to create explosives. Will it be possible for them to re-create any explosive ?

  2. If yes, then what is the basest explosive that they can create ? Basest means minimum expertise and using naturally available materials. It would be appreciated if you could provide some details, like detonation time, impact, maximum capacity or such.

  3. As a special case, can gunpowder be completely eliminated ?

Apologies for any formatting issues, I'm using the Android app, feel free to correct any errors you see.


It is quite possible that a small isolated group could lose the ability to manufacture explosives, even if they retain awareness that they exist. Especially if it has been long enough (decades?) for all the surviving ammunition to be expended and firearms to be broken/worn out. Without the ability to work metal or salvage remnant technology, gunpowder by itself is of little value. Wooden or clay grenades are not nearly as effective as metal ones and without steel a firearm type device is a death trap (so cast iron, bronze, or whatever isn't going to make a good arquebus).

Bows and crossbows were more effective than firearms for centuries after the introduction of gunpowder, especially bows, but they required a lifetime of training to be effective. In your scenario it is highly likely that the survivors took to bows early on due to a scarcity of firearms and ammunition and now most, if not all, people should be effective with them. It would be a tall order to get an archer to use a cobbled together firearm or to throw a clay pot with a smoking fuse. Of course crafting serviceable bows and arrows is also a skilled task, so they are probably hording compound bows and manufactured arrows from the past as well.

Most types of explosives degrade over time, so stockpiles of TNT and the like won't be very stable and would be avoided. Most fertilizer (a great base for explosives) really became prevalent once atmospheric extraction of nitrogen made them cheap, in your scenario this wouldn't be the case and the survivors would be dependent on harvesting minerals from the ground. That kind of specific knowledge is very perishable. LITERACY is perishable, there is a reason why almost the entire world was illiterate until very recently. In your scenario it seems likely that teaching the youth to read, versus oral transmission of essential life skills, would take a back burner and be mostly lost. So you'd be hoping that a chemist, engineer, or STEM professor was in the survivor mix, otherwise even literate folks without the appropriate technical background would be forced to choose to experiment with explosives versus some other pressing task like agriculture, creating antibiotics, clean water, food storage, etc, all those other things that can be much more immediately demanding of a low technology society.

Without the internet, and assuming the loss of almost every electronic data repository, it would be unlikely that a band of survivors, building a town from scratch, would have access to the printed materials they would need unless they are rebuilding on top of a town with a decent university library. Few folks would choose a thick chemistry or geology textbook instead of water, food, ammo, and medicine when they evacuate. Expeditions to retrieve textbooks would be essential, once the basics of survival are met, but of course if they are not near a place that has a surviving library they are SOL. Most casual books found in bookstores and the like are not very helpful in ACTUALLY making explosives, they explain the concepts but don't go into great detail (hence the fervor over "The Anarchists Cookbook" when it came out). Military manuals would be great, but of course most of them are probably radioactive by now :)

  • $\begingroup$ I tend to agree with this. I feel like the other answers were maybe a bit overly optimistic about how easy it would be. The loss of life = loss of knowledge, loss of access to resources etc. Its no small thing to create a modern explosive. This isn't to say it couldn't and wouldn't be done but it would be difficult and probably not the primary concern of survivors $\endgroup$ – James Jul 12 '16 at 17:13
  • $\begingroup$ Heck, modern folks wouldn't even have medieval level technology if they lost everything. Most people have no idea how to make cloth or building materials, much less clothing and buildings. Many wouldn't be able to identify what's edible without a label. The groups of people who survive more than a short while are going to have a lot of specialized knowledge available. $\endgroup$ – Seeds Jul 12 '16 at 21:31
  • $\begingroup$ I've of the opinion that many folks could live off the "bones" of modern society until the canned food, ammo, and batteries run out. With several thousand survivors it is pretty likely that some farmers, hunters, and STEM types made it. Given time they could reproduce a lot of stuff, but WHY would they? Explosives, even gun powder, have a lot of associated sister technologies that need to be there, and I doubt it will be high on the priority list. Now if they had a stockpile of flintlock rifles for some reason, different story. Maybe they raided Dixie gun works? $\endgroup$ – Jason K Jul 13 '16 at 13:31

Will we be able to make explosives again? Yes, and quickly too

The reason humans did not make any explosives until the Common Era is not because it is hard, but because we did not know how.

Apocalypse by all means but unless you eradicate all the relevant knowledge we have accrued thus far — that is to say: burn every chemistry book in existence — then there are several options open to make explosives.

...to mention but a small handful.

The Apocalypse cannot reverse time. In order to return to a previous state of ignorance, you must eradicate knowledge, and that is a very difficult thing to do.

So: yes, explosives can soon be made again, and no, there is no way you can stop this unless you round up every chemistry book in the world and burn them.


Gunpowder is a mix of sulfur, charcoal and saltpeter - all naturally occurring elements. There's no way to eliminate that unless something removes one of its ingredients completely. Gunpowder is also the first explosive anyone would discover/rediscover. Especially if they know that "in the old times we used to have gunpowder".

Gunpowder detonates immediately after it is heated enough (usually by a spark or a flame). Explosive force depends on the amount used. I have no idea what you mean by "maximum capacity". You can produce as much gunpowder as you have sulfur/charcoal/saltpeter.

  • 1
    $\begingroup$ The ingredients for making gunpowder are sulfur, charcoal, saltpeter, and knowing how to make gunpowder. It's the last one that apocalypses tend to eliminate. $\endgroup$ – candied_orange Jul 12 '16 at 7:41
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    $\begingroup$ @CandiedOrange sure, but it's also relatively easy to gain it again. Gunpowder wouldn't have been discovered in the first place otherwise, and with the knowledge that gunpowder exists at all you've got a further advantage over the original discoverers. $\endgroup$ – Annonymus Jul 12 '16 at 7:46
  • $\begingroup$ Gunpowder doesn't actually explode, it burns vigorously. It only "explodes" as such if in a confined space. $\endgroup$ – Separatrix Jul 12 '16 at 8:19
  • $\begingroup$ @Separatrix that's right, but it's the easiest way of making explosives, even if it isn't necessarily by itself an explosive. (thanks for correcting the misspellings/typos I missed btw) $\endgroup$ – Annonymus Jul 12 '16 at 8:20

There are sugar based explosives that are much easier to make than gun powder. You could simply let someone remember it vaguely and experiments until finding a repeatable method.

  • $\begingroup$ I may be wrong here but I think that only works with refined sugar, which is difficult to produce with medieval-level tech. Also, without international trade, sugar may not be obtainable where the characters of the story live. $\endgroup$ – Annonymus Jul 12 '16 at 7:47
  • $\begingroup$ I'm not a chemist so cannot comment if the crude sugar would do the same effect. But I believe sugar is available since the ancient times. Obviously it would depend on the region. $\endgroup$ – Cem Kalyoncu Jul 12 '16 at 10:50
  • $\begingroup$ yes, that was what I meant. While, obviously, sugar can be cultivated easily enough, not every region is suitable for sugar, and without high-volume international trade it would be difficult to find sugar in a region that is far from another region which can produce it. I'm not actually sure where sugar thrives, but, if, for example, the story is set in iceland (I'm prettu sure sugar can't be cultivated there) they probably wouldn't have access to sugar. $\endgroup$ – Annonymus Jul 12 '16 at 10:57
  • $\begingroup$ @Annonymus Sugar can be refined from many sources, not just sugar cane. The knowledge to do so would have to be there but you can refine sugar from corn, fruits etc. $\endgroup$ – James Jul 12 '16 at 17:14

I doubt knowledge of explosives would be lost. The advanced ones, and perhaps manufacturing for the more complex ones, would be quickly left behind. But, the knowledge that we had them, and some of the things that could be done with them - from guns and bombs to mining and demolition, there would be too many uses not to try to recreate explosives eventually. Most people would remember that explosives existed, and perhaps a little of what they could be used for, even if they don't remember chemical formula and manufacturing - and such stories would linger for generations and inspire people to experiment, unless some very specific targeting of people with that knowledge was going around.

Additionally, there would be large chunks of the population that do know enough to recreate, at least, gunpowder - including survivalists, reenactors, history buffs, storybook readers (certain kinds of medieval-ish or fantasy has reasonable clues), and the randomly curious. Some of these people would be more suited to survive than others - but some might end up in a pretty good position to spread that knowledge around. Some of those skills - survival skills, ways of hand-crafting any kinds of useful supplies, preserving, are all going to be immediately valuable enough that people will make time to keep knowledge alive, even bits that are a little more useful for the future. People would also be scrounging for useful knowledge - including books that would contain those intermediate skills that will allow people to make the jump from food/water/shelter to rebuilding an advancing civilization. It is possible a given group might not contain any of them, though the high proportion of other useful skills they could offer makes that a little less likely.

As for what would get rediscovered first... gunpowder is a reasonable guess, which can be made by experimenting with mixes of charcoal, sulfur, and saltpeter - all of which are naturally occurring, and two of which anyone knows what it is when they find it and two of which can be created anywhere (knowledge of saltpeter is the limiting ingredient, I think, but it forms naturally in stables). Put it under pressure and set it on fire, and there you go. boom. This is among the most likely of the explosives to be remembered.

Another possible guess might be flour (or sawdust or the like) creating a dust explosion - this would probably be more useful for signaling or scaring people away than causing damage, since it depends on igniting the suspension of the particles in the air. However, it depends on nothing people can't immediately get their hands on, and it only takes one vague-ish recollection that it can be done (or a bakery or mill fire) to get the point across. On the other hand, if someone manages to hang onto a bit more knowledge, then guncotton or nitrocellulose might be a fairly good explosive to keep on hand - it requires cellulose (paper or cotton) and nitric acid - and if you've got saltpeter, you can get nitric acid.

It might take a while for the explosives to actually get reestablished - depending on when they have luxury time to experiment, instead of pure survival. But any group that knows the recipe (or any other handicraft skills) would do their best not to let it get lost, because those skills will be invaluable once the group has managed any stability at all to think about the future. If they can reach medieval level, or even pioneer level, they will probably be experimenting with explosives or crude chemistry. If they're stuck at hunter-gatherer level, it might take longer get around to it.

If you don't want explosives, you might start with a group which didn't have anyone knowledgeable to begin with, or no one remembered what saltpeter was, or set the story in the time before they got around to experimenting yet. Or have someone deliberately working to deny knowledge of explosives, for whatever reason. All of these will slow down the re-discovery of explosives... I just don't think it will stop people from eventually figuring something out. Like I said, there will too many people who remember what useful things can be done with them, to keep people experimenting.


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