Where did the most significant changes from feudalism to monarchy take place during this period?

The most significant changes from feudalism to monarchy primarily took place in Western Europe, particularly in countries such as:

1. France: The Capetian Dynasty centralized power, gradually diminishing feudal lords' authority and enhancing the monarchy's role.
2. England: After the Norman Conquest in 1066, William the Conqueror implemented a feudal system that laid the groundwork for the transition to a more centralized monarchy.
3. Spain: The unification of the crowns of Castile and Aragon in the late 15th century marked a shift away from feudal allegiances towards a centralized monarchy.
4. Central and Eastern Europe: The Holy Roman Empire saw various attempts at centralization, although it remained largely feudal for an extended period.

Overall, the movement towards monarchy involved the consolidation of power by kings, the establishment of bureaucracies, and the decline of feudal loyalties, which shaped modern nation-states.