Ferdinand II (10 March 1452 – 23 January 1516), also known as Ferdinand the Catholic (Spanish: Fernando el Católico), was King of Aragon from 1479 until his death in 1516. As the husband and co-ruler of Queen Isabella I of Castile, he was also King of Castile from 1475 to 1504 (as Ferdinand V). He reigned jointly with Isabella over a dynastically unified Spain; together, they are known as the Catholic Monarchs. Ferdinand is considered the de facto first king of Spain, and was described as such during his reign, even though, legally, Castile and Aragon remained two separate kingdoms until they were formally united by the Nueva Planta decrees issued between 1707 and 1716.
The Crown of Aragon that Ferdinand inherited in 1479 included the kingdoms of Aragon, Valencia, Mallorca, Sardinia, and Sicily, as well as the Principality of Catalonia. His marriage to Isabella is regarded as the "cornerstone in the foundation of the Spanish monarchy". They played a major role in the European colonization of the Americas, sponsoring the first voyage of Christopher Columbus in 1492. That year, the couple defeated Granada, the last Muslim state in Western Europe, thus completing the centuries-long Reconquista.
Following Isabella's death in 1504, the couple's daughter Joanna became queen of the Crown of Castile. That year, after a war with France, Ferdinand conquered the Kingdom of Naples. In 1507, he became regent of Castile on behalf of Joanna, who was alleged to be mentally unstable. In 1506, as part of a treaty with France, Ferdinand married Germaine of Foix, with whom he had no surviving children. In 1512, he conquered most of the Kingdom of Navarre, ruling all the territories comprising modern-day Spain until his death in 1516. He was nominally succeeded by his daughter Joanna, but power was soon assumed by her son Charles I (later Holy Roman Emperor Charles V).
Ferdinand was born on 10 March 1452 in the town of Sos del Rey Católico, Kingdom of Aragon, as the son of John II of Aragon (whose family was a cadet branch of the House of Trastámara) by his second wife, Juana Enríquez.
Ferdinand married Isabella, the half-sister and heir presumptive of Henry IV of Castile, on 19 October 1469 in Valladolid, Kingdom of Castile and Leon. Isabella also belonged to the royal House of Trastámara, and the two were second cousins by descent from John I of Castile. They were married with a clear prenuptial agreement on sharing power, and under the joint motto "tanto monta, monta tanto". He became jure uxoris King of Castile when Isabella succeeded her deceased brother in 1474. The two young monarchs were initially obliged to fight a civil war against the Queen of Portugal Joanna la Beltraneja, the purported daughter of Henry IV, and were swiftly successful. When Ferdinand succeeded his father as King of Aragon in 1479, the Crown of Castile and the various territories of the Crown of Aragon were united in a personal union. The various states were not formally administered as a single unit, but as separate political units under the same monarchs. (The legal merging of Aragon and Castile into a single Spain occurred under Philip V in 1707–1715.)
The first years of Ferdinand and Isabella's joint rule saw the Spanish conquest of the Emirate of Granada, the last Islamic al-Andalus entity on the Iberian peninsula, completed in 1492.
The completion of the Reconquista was not the only significant act performed by Ferdinand and Isabella in that year. In March 1492, the monarchs issued the Edict of Expulsion of the Jews, also called the Alhambra Decree, a document which ordered all Jews either to be baptised and convert to Christianity or to leave the country. It allowed Mudéjar Moors (Islamic) and converso Marrano Jews to stay, while expelling all unconverted Jews from Castile and Aragon (most Jews either converted or moved to the Ottoman Empire). 1492 was also the year in which the monarchs commissioned Christopher Columbus to find a westward maritime route for access to Asia, which resulted in the Spanish arrival in the Americas.
In 1494, the Treaty of Tordesillas divided the entire world beyond Europe between Portugal and Castile (Spain) for conquest and dominion purposes – by a north–south line drawn down the Atlantic Ocean.
Ferdinand abrogated a section of the 1491 Treaty of Granada peace treaty in 1502 by dismissing the clearly guaranteed religious freedom for Mudéjar Muslims. Ferdinand forced all Muslims in Castile and Aragon to convert, converso Moriscos, to Catholicism, or else be expelled. Some of the Muslims who remained were mudéjar artisans, who could design and build in the Moorish style.
The latter part of Ferdinand's life was largely taken up with disputes with successive kings of France over control of Italy, the Italian Wars. In 1494, Charles VIII of France invaded Italy and expelled Alfonso II, who was Ferdinand's first cousin once removed and step nephew, from the throne of Naples. Ferdinand allied with various Italian princes and with Emperor Maximilian I to expel the French by 1496 and install Alfonso's son, Ferdinand II, on the Neapolitan throne. In 1500, following Ferdinand II's death and accession of his uncle Frederick, Ferdinand signed an agreement with Charles VIII's successor, Louis XII, who had just successfully asserted his claims to the Duchy of Milan, to partition Naples between them, with Campania and the Abruzzi, including Naples itself, going to the French and Ferdinand taking Apulia and Calabria. The agreement soon fell apart and, over the next several years, Ferdinand's great general Gonzalo Fernández de Córdoba fought to take Naples from the French, finally succeeding by 1504.
The King of France complains that I have twice deceived him. He lies, the fool; I have deceived him ten times and more.
Some time before 1502, Andreas Palaiologos, the last exiled claimant to the Byzantine throne of his house, sold his titles and royal and imperial rights to Ferdinand. Those, however, had never been made use of, due to the doubtful nature of the deal.
Isabella made her will on 12 October 1504 in advance of her death on 26 November 1504. In it, she spelled out the succession to the Crown of Castile, leaving it to Joanna and then to Joanna's son Charles. Isabella was dubious of Joanna's ability to rule and was not confident of Joanna's husband Archduke Philip. Ferdinand moved quickly after his wife's death to continue his role in Castile. On the day of his wife's death, he formally renounced his title as King of Castile and instead became governor (gobernador) of the kingdom as a way to become regent. Philip deemed his wife sane and fit to rule. A compromise was forged between Philip and Ferdinand, which gave Ferdinand a continued role in Castile. Ferdinand had served as Joanna's regent during her absence in the Netherlands, ruled by her husband Archduke Philip. Ferdinand attempted to retain the regency permanently, but was rebuffed by the Castilian nobility and replaced with Joanna's husband.
In the Treaty of Villafáfila of 1506, Ferdinand renounced not only the government of Castile in favor of Philip but also the lordship of the Indies, withholding half of the income of the "kingdoms of the Indies". Joanna and Philip immediately added to their titles the kingdoms of Indies, Islands and Mainland of the Ocean Sea. But the Treaty of Villafáfila did not hold for long because of the death of Philip; Ferdinand returned as regent of Castile and as "lord of the Indies".
The widowed Ferdinand made an alliance with France in July 1506 and married Germaine of Foix, cementing the alliance with France. She was the granddaughter of his half-sister Queen Eleanor of Navarre and niece of Louis XII of France. Had Ferdinand's son with Germaine, John, Prince of Girona, born on 3 May 1509, survived, "the crown of Aragon would inevitably been separated from Castile" and denied his grandson Charles the crown of Aragon. But the infant Prince John died within hours and was buried in the convent of Saint Paul in Valladolid, Kingdom of Castile and Leon. He was later transferred to Poblet Monastery, Vimbodí i Poblet, Principality of Catalonia (Crown of Aragon), traditional burial site of the kings of Aragon.