I am writing a book where the world is split into multiple kingdoms, with each kingdom using a similar magic system to the rest, but using different powers. IE one can control the elements, another does telepathy, another mostly powers associated with the dead, etc.
Is there are any way, assuming the world has progressed via a combination of industry coupled with magic, for guns to not really be a common weapon in war? Or I suppose more specifically, what circumstances - ie cultural reasons, lack of specific resources being available, etc - might have led to the traditional close-quarters army vs army combat remaining prevalent despite the technological advancement?
Crossbows and siege machines such as trebuchets are fine. And of course, if you have suggestions for how armies might be able to defend themselves against magic to allow for such large-scale ground warfare, I'm all ears!