In France, feudalism began to develop in the 10th century, and by the middle of the 11th century many “unemployed” knights had accumulated, ready to fight anywhere. In England, the Norman conquest of 1066 created many internal problems. Until they were resolved (by the end of the 12th century), the Norman masters of England did not have extra strength for the crusades, but many dispossessed Anglo-Saxons went on a crusade and did not return to their homeland.
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.