Final answer:
The unification of England, France, and Spain was due to the consolidation of power by their monarchies.
Step-by-step explanation:
The reason why England, France, and Spain were able to unify while the Italian states and the Holy Roman Empire struggled lies in the foundations of these new nation-states. The key foundation of the successful unification of England, France, and Spain was the consolidation of power by their respective monarchies. In England, the Tudor dynasty brought stability and increased centralization under the rule of Henry VII and subsequently Henry VIII. In France, the Capetian dynasty and later the Valois dynasty established strong centralized control over the feudal nobility. In Spain, the marriage of Ferdinand of Aragon and Isabella of Castile formed a united monarchy that sought to consolidate power and promote Catholicism.
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