It was actually confusing for me too. The time (year) wasn't clearly identified. It would be easier to understand the flow of the story if the time was identified. It seemed to be that they're advancing too fast.
In the field of medicine, they are already using scalpes and some medical equipments. The scalpel was first made at 1915 and such equipments shouldn't look like that; if they we're to use equipments as such it shall not look like that.
In the field of war Nicholas and his men used guns and cannons while Prince Linden and his army used swords. It was an obvious fact that a difference between a gun and sword is to high. If you would think, a bullet is not something you could easily dodge and defend yourself from. Yet the prince's army managed to fight the despite the difference.