The Origins of Magic

After four years since transmigrating, Les could only toil desperately in the military camp. At last, he returns to civilized society, carrying his hatred with him.

The parliamentary republic in the south is breaking through the blockade, while the nobles in the north are ambitious. A new era is about to begin. With his dreamlike floating city, Les steps into this unfamiliar world and gives his first cry…

This is a slow-burn story, with a setting I consider plausible. It's not a straightforward power fantasy.