Ferdinand V and Isabella: Spanish Monarchs

Ferdinand (1452–1516) and Isabella (1451–1504) united Castile and Aragon creating modern Spain under a dual monarchy.

Ferdinand was born at Sos, Aragon, on March 19, 1452, as the son of John II of Aragon and Navarre (1397–1479) and Juana Enriquez, his second wife. As heir to the throne of Aragon, Ferdinand became king of Sicily in 1468. He was skillful, ruthless, ambitious, self-centered, and political in all his endeavors.

Ferdinand married his equally ambitious, pious, but wiser cousin Isabella of Castile and León. She was born at Madrigal de las Torres in Castile on April 22, 1451, the daughter of feeble-minded King John II of Castile and León (1405–54) and Isabelle of Portugal, his strongminded second wife. She inherited an extensive royal lineage from several generations of European dynasties. The couple maintained exceptionally close ties to the papacy.

When Ferdinand’s father died in 1479, Ferdinand and Isabella’s union merged the two largest kingdoms of the Iberian Peninsula and created 90 percent of present-day Spain. The astute Isabella insisted that there be joint rule and that she govern Castile herself.

The saying “Tanto monta, monta tanto” (They are one and the same), became their motto. Isabella also insisted that both their names be placed on each royal document and that she preside at each state transaction. She also allowed their coat of arms to be united. The couple had five children: Isabella of Aragon (1470–98), Juan of Aragon (1478–97), Juana of Castile (1479–1551), Maria of Aragon (1482–1517), and Catherine of Aragon (1485–1536).