Ferdinand THE CATHOLIC, V. of Castile, II. of Aragon and Sicily, and III. of Naples, was born at Sos in Aragon, 10th March 1452, the son of John II. of Navarre and Aragon. By his father he was formally associated in the government of Aragon in 1466, and appointed king of Sicily in 1468; in 1469 he married, at Valladolid, Isabella, sister of Henry IV. of Castile. On Henry's death in 1474 most of the nobles refused to acknowledge the legitimacy of his daughter Juana ('La Beltraneja'), and proclaimed Isabella and her husband Ferdinand joint-sovereigns, who, in 1479, emerged victorious from the civil war that ensued. In that year also Ferdinand became king of Aragon on the death of his father, and the two kingdoms of Aragon and Castile were united in the persons of Ferdinand and Isabella; the latter, however, as long as she lived, maintained control and authority in Castilian affairs. The reign that followed is one of the greatest in the history of Spain, which was in a few years advanced to the first rank among the nations by the military, administrative, and diplomatic skill of its sovereigns, and of the distinguished body of ministers and generals that surrounded them.
Ferdinand's political talents found plenty of scope in the distracted condition of affairs which met him on his accession—the kingdom split into factions, feuds raging between the great houses, and robbery and outrage rife in every quarter of the country. The effectual suppression of the banditti he accomplished by reorganising the santa hermandad, or 'holy brotherhood,' a kind of militia-police, composed of the citizens and the country-people. Moreover, a principal aim of Ferdinand and Isabella was to break the power of the feudal aristocracy, and good use was made of the hermandad in carrying out this design. The establishment of the Inquisition in 1478–80, although primarily and mainly intended to further 'religious' ends, likewise helped to lessen the nobles' influence; and Ferdinand also strengthened his power by vesting in himself and his successors the grand-mastership of the military orders of Calatrava, Alcantara, and Santiago. In all his schemes he was ably seconded by his queen and by the celebrated Cardinal Ximenes.
The year 1492 was the most brilliant in his reign. It opened with the fall of Granada, which marked the end of the long struggle with the Moors; and in August Columbus set sail from Palos. Although the free exercise of their religion was guaranteed to the Moors, an edict for the expulsion of the Jews from the conquered kingdom was immediately signed; and, a few years after, the privileges secured to the Moors were treacherously withdrawn, baptism or exile being offered as alternatives. By these two barbarous and unwise acts the most industrious and civilised inhabitants of the Peninsula were driven from it. The discovery of America, however, for a time gave Spain almost unchallenged supremacy along both shores of the Atlantic, and Ferdinand turned his attention to European affairs. From France he recovered by treaty the counties of Rousillon and Cerdagne (now the Pyrénées Orientales), which his father had mortgaged to Louis XI.; in 1495 he formed the Holy League, with the pope, the emperor, and the states of Milan and Venice (Henry VII. of England was persuaded to enter the league nearly sixteen months later), under which Gonzalvo de Cordova drove the French out of Naples; and in 1500–1 the French king was induced to join him in the conquest and partition of Naples, only to be overreached by the Catholic king, and compelled to yield up the kingdom to him entirely three years later.
In 1504 Isabella died, and Ferdinand at once had his insane daughter Juana proclaimed queen of Castile, and himself regent; but Juana's husband, the Archduke Philip of Austria, threatening an appeal to arms, the king threw up the regency, and in 1505 married Germaine de Foix, a niece of Louis XII. of France. Philip died in September 1506, only three months after his landing in Castile; whereupon Ferdinand resumed the administration, which he retained till his death, although his position was greatly changed after Isabella's death, and he was compelled to reverse all his former policy—make an alliance with France, and buy off French claims on Naples—besides being frequently in great straits for money, so that he was for some time unable to send the second portion of the dowry required to secure the marriage of his daughter Catharine with Henry, Prince of Wales. Nevertheless, he took part in the famous league of Cambrai formed against Venice in 1508, conquered Oran in Africa in 1509, and in 1512 seized a favourable opportunity to make himself master of the long-coveted kingdom of Navarre—thus becoming monarch of Spain from the Pyrenees to the Rock of Gibraltar. He died at Madrigalejo, 23d January 1516, and was succeeded by his grandson, best known in history as the Emperor Charles V. Ferdinand's ability, both as a general and as a statesman, has been variously estimated; but at least his skill and shrewdness as a negotiator were unsurpassed in an age of cunning and unscrupulous diplomatists. A characteristic anecdote relates that, on hearing of a complaint made by Louis XII. that he had cheated him once, he promptly answered: 'He lied, the drunkard! I cheated him three times.' Yet to Ferdinand and Isabella Spain owes her unity and greatness as a nation, and under them the foundations were laid of the unrivalled and imperial influence which, in the brilliant reign of their successor, she exercised over Europe. See Prescott's History of the Reign of Ferdinand and Isabella (3 vols. Boston, 1838).