For my current world, I have a continent whose countries were brought together into a single, massive empire. After the death of the last emperor, the central imperial authority crumbled and the constituent regions continued their association through the formation of a federation.
Each region, prior to the rise of the empire, was ruled by an absolute monarch whose title came via inheritance. The central imperial authority allowed the monarchs to continue to govern if they swore allegiance to the emperor. The imperial authority also decreed that each and every monarch must have training in the use of magic. This requirement has persisted to the modern day in the kingdoms of the federation.
My issue is, I can't think of a single, dominant reason for which this condition would be mandated and continue to persist after the fall of the empire.
What would be so widespread to apply to every part of a continent and persistent enough to last for at least a millennium that would require and perpetuate the need for rulers to be trained in the use of magic?
A few notes:
- Magic in this world is not a common thing.
- Those who can use magic are mostly of low power, such as struggling to light a candle.
- There is no common or well-known manner in which to influence others via magic.
- The continent is about the size of North and South America combined.
- An abundance of magical creatures did not exist until long after the formation of the empire.
- The ability to use magic is not genetic, but the limit of one's power is.