This was from our huge spam thread a while back (Ronin probably remembers):
First map is of the era of the Great Wars, which was two hundred or so years of trench warfare, medieval style, with automatic crossbows, flamethrowers, Chinese-style rockets, and good old-fashioned swordfighting between my conworld's concultural equivalents of the Byzantines (Aidis) and Tang/Song Dynasty China (Cedarin/Kensalus) and their vassals/allies.
I forgot to mention the invention of primitive canons/gunpowder and clockpunk technology (aka Da Vinci tanks) towards the last half a century of the Great Wars which somewhat turned the tide against the Cedarinians and their allies, but that still isn't as awesome as machine-gun crossbows. Also, it isn't exactly like trench warfare per se in the sense that cavalry were still useful... as long as they had shitloads of flamethrower-resistant armor on, and if they were attacking a position weak in crossbowmen. Or something like that.
Anyhow, according to most historians of my conworld, the reason crossbow trench warfare was developed was because of the Rule of Cool. On a more serious note, this was really just Rule of Cool, even more so than me handwaving the co-existence of primitive rifles and swords/crossbows in the later history of my conworld. I suppose arguably much of it would be the same reason why trench warfare developed in our world, i.e., there are big empires with lots of resources and people who have recently made lots of technological breakthroughs which render traditional tactics of charging across open fields useless. Although frankly to be honest I'm not 100% sure, because after this the style of trench warfare gradually becomes obsolete due to newer gunpowder weapons being able to blast apart the trenches... somehow. And crossbow-resistant armor. Or some rule of cool bullshit.
Basically trench warfare medieval/clockpunk style. Rule of cool rules over rule of reality.
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