PrepMo 2023 Day 17 Cultural setting

This society is a mix of mages and non-magical humans. The dominion is run by Lord Shadowbane. He rules through fear and control is overly important to him. He refuses to acknowledge magic in his kingdom. In his youth, he lost what he felt was his one true love to a mage with fire powers. Since coming into power he has put in place a strict rule that no magic will be used in his kingdom. He has imprisoned people for suspicion of using magic. He has killed for the same offense. Of course, he does none of the killing. He keeps his hands clean up in his large castle. He is very far removed from the land below over which he rules.
This story is set in medieval times, so technology is extremely limited. Electricity and steam power have yet to be invented. Medicine is comprised of potions and medicinal herbs.
The setting is crucial to the story and the antagonist, Icerna. Shadowbane is the monarchist in control of all. He imprisons anyone and everyone who may disagree with him. Disagreeing with him solidly and publicly can mean isolation in prison – or worse.
The setting also impacts the plot, as the kingdom is vastly isolated. This means there will be no outside help. The mages must find a way to rise up together, putting aside their differences, against a formidable opponent.