So, a council of wizards decided that all should bow to their rule. That, it turns out, is a thing wizard councils did a lot. This lead into a certain degree of disagreement, which in turn resulted in the exchange of increasingly large fireballs and generally propelling matter into the stratosphere.

So, now most of the larger objects in the stratosphere have fallen down, leaving only sooty smoke and dust darkening the skies, resulting in a nuclear winter. And, given the aforementioned fireballs, a lot of the wizards are gone, and anyone pursuing the craft tends to end up under considerable time-pressure to learn how to stand on thin air.

So, my question is: How, if at all, can a medieval fantasy population, with a bare minimum of magic, weather the nuclear winter?

For a medieval world an harsher climate would easily mean famine: look at the impact of the year without summer following the Krakatoa eruption on some communities, though they were well off of middle age.

A nuclear winter would mean sure death for a large part of the population. The only way for magic to help would be to increase food production before the blow, and to preserve the food during the nuclear winter.

Did you know that temperatures dipped in Medieval times in something close to Nuclear Winter? It was called the Little Ice Age. NW takes temps down by 1.8 degrees F. The LIA took it down by 1.5 degrees Fahrenheit. Unless you are looking to add NW ON TOP of that--gotta say, historically, you ALREADY HAVE the effects, or at least pretty close.

So Famine. And yet the population still grew as people adjusted. There's a .3 difference. That's a lot.

NW, or at least the 1.8 takes 100 Hiroshimas. That's just...a lot. And difficult to achieve for a population so low. It means that there have to be whole areas that are just burned to ash.

Considering the population of Medieval times, this means a LOT of wizards. In fact, to achieve 100 Hiroshimas, I wonder that there would be all that many people to oppress considering all the wizards needed to do this. Further, it would NOT happen all at once--Hiroshima was a one time event, as are most nuke drops. What you're talking about (massive fires and ash in the atmosphere) will likely NOT happen all at once. Medieval times were fractured as far as communication and travel is concerned--so it's not like it is now. Concerns are local. The wizards would be warring over time, not all at once. Which means that the drop is going to be more gradual than it would be if you did 100 Hiroshimas.

The amount needed to be burned is on a scale that is far over what Medieval times could achieve. Total destruction of a city is definitely not the way war was waged most of the time. Because you wanted to take territory and resources. War waged as it has been in modern times is very, very different.

The destruction of Hiroshima was about 5 square miles. With a lot of material to burn. The largest city in England, London, was maybe 1.12 square miles. And this was a mega city of the time. That's the main problem with the premise

The answer to how they can weather it--hie thee to yon google and ask about the effects of the Little Ice Age. Folks died, famine happened and so on. That can give you a detailed account.

I will add to this when I have time regarding the Great Famine and effects.

Thing one that happened was a shift in weather patterns--specifically far more rain than was good for crops. Lots of things died.

If the temperature continued to drop, this would worsen (less rain eventually, some more extreme weather).

People would die, but people would also adjust. No matter how much the technology lacked. I posit that wizards might not be blamed for this directly (cause and effect wasn't a strong suit of the Medieval mind) and that magic would be used like technology is to help US survive.

See, even if 100 Hiroshimas happened, though there would be groups that "blamed science" most humans would grasp at ANY advantage to help them survive, even the very science and tech that destroyed them. That's how they survive. A few folks with hedge magic helping their town survive and making things grow...

Survive? Sure!

There were farmers in Sicily just as there were farmers in Norway. The difference in temperature is easily more than the effects of a nuclear winter.

Some problems with that glib answer:

• Farmers in Norway and in Sicily have animals and crops adapted to their respective climate. They know what to expect and how to cope. That's not the case in a surprise magical winter. There may well be near 100% losses of the planted crops and herds.


• Buildings will not be adapted to the temperature. Will orchards be cut down to heat thin-walled huts? Will roofs collapse under the loads of snow?


• If half the necessary food is missing, it won't be that half the people will simply lie down and starve. There will be a collapse of law and order.

Still, exterminating an entire population is extremely difficult. The question is how many will survive, and who. One percent? Ten percent?

• Who has stockpiles of food, and can they defend them? Will people die before they can consume their hidden stockpiles, and will subsequent scavengers find them?


• Are the barons ruthless enough to let their serfs starve and to feed their knights? Are they ruthless enough to let some of their knights starve to feed some of their serfs?


• Will groups like hunters and fishermen continue to feed their communities as long as possible, or will they hide out in the forest with their meager catch?

I can think of a couple of spells that a low-end "hedge wizard" or "wise woman" might know.
Lure fish into creel.
Detect wild fruit and vegetables. (Might also work on hidden root cellars.)
Preserve meat. (If fodder runs out and animals must be slaughtered.)
Ignite fire with wet wood and no tinder. (After the rains.)