Why were the rich townspeople in the Christian states of the Iberian Peninsula obliged to acquire a war horse and weapons? Was there such a rule in cities in other European countries?
This was due to the needs of the Reconquista. This rule did not exist in other countries, since there it was necessary to pay taxes with the help of which armies were assembled.
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.