Answer:
Ferdinand II of Aragon
Explanation:
Son and future heir of John II of Aragon and Joan Enriquez, Ferdinand of Aragon was born in 1452. At that time, the likely successor to the throne of Aragon was his older brother, Prince Charles, the result of his father's first marriage to Blanche de Navarre. In 1461, however, he died mysteriously, probably poisoned by his stepmother, and young Ferdinand became heir. He married Princess Isabel in 1469. He assumed the throne with the death of his father (1479) after a prolonged civil war (1474-1479) in the kingdom of Castile, thus establishing the dynastic union of Aragon and Castile, the institutional basis of modern Spain.
