known as Ferdinand the Catholic. 1452–1516, king of Castile (1474–1504); as Ferdinand II, king of Aragon (1479–1516) and Sicily (1468–1516); as Ferdinand III, king of Naples (1504–16). His marriage to Isabella I of Castile (1469) led to the union of Aragon and Castile and his reconquest of Granada from the Moors (1492) completed the unification of Spain. He introduced the Inquisition (1478), expelled the Jews from Spain (1492), and financed Columbus'voyage to the New World