LOLl how tf I see that masterpice comment now

Ferdinand II of Aragon, the grandson of Ferdinand I, and Queen Isabella I of Castile were married in 1469, later taking the title the Catholic Monarchs; subsequently, this event was seen by historiographers as the dawn of a unified Spain. At this time, though united by marriage, the Crowns of Castile and Aragon maintained distinct territories, each keeping its own traditional institutions, parliaments, laws and currency.[36] Castile commissioned expeditions to the Americas and benefited from the riches acquired in the Spanish colonisation of the Americas, but, in time, also carried the main burden of military expenses of the united Spanish kingdoms. After Isabella's death, Ferdinand II personally ruled both crowns.

By virtue of descent from his maternal grandparents, Ferdinand II of Aragon and Isabella I of Castile, in 1516 Charles I of Spain became the first king to rule the Crowns of Castile and Aragon simultaneously by his own right.