What mostly directly contributed to the strengthening of monarchs in England France and Spain during the late Middle Ages?

The strengthening of monarchs in England, France, and Spain during the late Middle Ages was primarily driven by the consolidation of power through centralized governance and the establishment of strong bureaucracies. The decline of feudalism, particularly following events like the Hundred Years' War, allowed kings to assert greater authority over their nobles. Additionally, increased taxation and the ability to raise standing armies further empowered monarchs, enabling them to maintain control and expand their territories. The support of the burgeoning middle class, who benefited from stable governance, also played a crucial role in reinforcing royal power.