He succeeded to relinquish suzerainty of his cousin Alfonso VII of León, becoming instead a subject of the papacy, as the kingdoms of Sicily and Aragon had done before him.

Several precursor kingdoms have had an Alfonso I.

Alfonso also moved the capital from Pravia, where Silo had located it, to Oviedo, the city of his father's founding and his birth.

Alfonso was the eldest son of Prince Francisco de Asis de Borbón-Dos Sicilias and Queen Isabel II, whose reign was marked by a constant political crisis which had several causes.

He assumed the title of Alfonso XII, for although no King of united Spain had borne the name " Alfonso XI ", the Spanish monarchy was regarded as continuous with the more ancient monarchy represented by the 11 kings of Asturias, León and Castile also named Alfonso.

Coming to the throne at such an early age, Alfonso had served no apprenticeship in the art of ruling, but he possessed great natural tact and a sound judgment ripened by the trials of exile.

Alfonso had two sons by Elena Armanda Nicolasa Sanz y Martínez de Arizala ( Castellón de la Plana, 15 December 1849 – Paris, 24 December 1898 ):

Alfonso and Ena had six children:

The marriage had been arranged by her father Alfonso VI of León in 1106 to unite the two chief Christian states against the Almoravides, and to supply them with a capable military leader.

Elena Lourie ( 1975 ) suggested instead that it was Alfonso's attempt to neutralize the papacy's interest in a disputed succession — Aragon had been a fief of the Papacy since 1068 — and to fend off Urraca's son from her first marriage, Alfonso VII of Castile, for the Papacy would be bound to press the terms of such a pious testament.

Generous bequests to important churches and abbeys in Castile had the effect of making the noble churchmen there beneficiaries who would be encouraged by the will to act as a brake on Alfonso VII's ambitions to break it — and yet among the magnates witnessing the will in 1131 there is not a single cleric.

After being widowed in 1327, Alfonso married in February 1329 Eleanor of Castile ( 1308 – 1359 ), who was betrothed to his brother James, who had refused to consummate the marriage.

In 1421 Queen Joan II of Naples, who had no children, adopted and named him as heir to the Kingdom of Naples, and Alfonso went to Naples.

When Sforza also abandoned Louis, Alfonso seemed to have all his problems solved ; however, his relationship with Joan suddenly worsened, and in May 1423 he had her lover, and a powerful figure in the Neapolitan court, Gianni Caracciolo, arrested.

Alfonso requested support from Braccio da Montone, who was besieging Joan's troops in L ' Aquila, but had to set sail for Spain, where a war had broken out between his brothers and the Kingdom of Castile.

Alfonso tried to regain the favour of the queen, but failed, and had to wait for the death of both Louis ( at Cosenza in 1434 ) and Joan herself ( February 1435 ).

As the Neapolitans had called for the French, Alfonso decided to intervene and, with the support of several barons of the kingdom, captured Capua and besieged the important sea fortress of Gaeta.

Papal troops had invaded the Neapolitan kingdom, but Alfonso corrupted the cardinal Giovanni Vitelleschi, who commanded them, and his successes waned.

This was because in 1448, while Skanderbeg was victoriously fighting off the Turkish invasions, three military columns, commanded by Demetrio Reres along with his sons Giorgio and Basilio, were dispatched to help Alfonso V defeat the barons of Naples who had rebelled against him.

Alfonso had been betrothed to Maria of Castile ( 1401 – 1458 ; sister of John II of Castile ) in Valladolid in 1408 ; the marriage was celebrated in Valencia on 12 June 1415.

Alfonso had been in love with a woman of noble family named Lucrezia d ' Alagno, who served as a de facto queen at the Neapolitan court as well as an inspiring muse.

The step-son of the deceased king, Alfonso VII of León, as reigning monarch and legitimate descendant of Sancho III of Navarre, put himself forward but garnered no local support.

Here she repudiated her earlier adoption of Alfonso and, with support from Martin V, named Louis III as her heir instead.

As King Alfonso of Naples was among the signatories of the treaty, Sforza also abandoned his long support of the Angevin pretenders to Naples.

However, Presidents Álvaro Arzú and his successors Alfonso Portillo, Óscar Berger and Álvaro Colom, have used a constitutional clause to order the army on a temporary basis to support the police in response to a nationwide wave of violent crime product of the Mexican criminal organizations going across the north-west region.

In order to avoid accountability, King Alfonso XIII decided to support the dictatorship of General Miguel Primo de Rivera, ending the period of constitutional monarchy in Spain.

Alfonso I ( king from 739-757 ) rallied Galician support when driving the Moorish army out of Galicia and an area of that was to become Leon.

The Pope's recognition of the claim to Naples of King Alfonso V of Aragon ( in the treaty of Terracina, signed by Eugenius at Siena somewhat later ) withdrew the last important support from the council of Basel.

The legend of St. James gained support during the reign of Alfonso II, when the Galician hermit Pelayo claimed to observe a mysterious brightness during several nights over the wood of Libredón, in Iria Flavia diocese.

Alfonso never even traveled to Germany, and his alliance with the Italian Ghibelline lord Ezzelino IV da Romano deprived him of the initial support of Pope Alexander IV.

Alfonso preferred to leave the throne to his grandsons, but Sancho had the support of the nobility.

With the support of king Jimeno Garcés of Pamplona, they drove Alfonso Fróilaz to the eastern marches of Asturias, and divided the kingdom among themselves with Alfonso Ordóñez receiving the crown of León and his elder brother Sancho being acclaimed king in Galicia.

The pope and king Louis IX of France favoured Alfonso, but both were ultimately convinced by the powerful relatives of Richard's sister-in-law, Eleanor of Provence, to support Richard.

Ottokar II of Bohemia, who at first voted for Richard but later elected Alfonso, eventually agreed to support the earl of Cornwall, thus establishing the required simple majority.

Others put forward included Alfonso VII, king of Castile, who as a foreign king found little support, and the choice of the Navarrese nobility, Pedro of Atarés, grandson of Sancho Ramírez, Count of Ribagorza, the illegitimate son of Ramiro I of Aragon.

In 1159 the young Alfonso was put briefly in the custody of García Garcés de Aza, who was not wealthy enough to support him.

In February, 1216, an extraordinary parliamentary session was held in Valladolid, attended by such Castilian magnates as Lope Díaz II de Haro, Gonzalo Rodríguez Girón, Álvaro Díaz de Cameros, Alfonso Téllez de Meneses and others, who agreed, with the support of Berengaria, to make common cause against Álvaro Núñez de Lara.

Since Mauregatus had ascended the throne in a coup d ' état with regional support in 783 and the succession of Bermudo proceeded without incident, it is probable that Mauregatus had procured a change in the ranks of the palatine nobility and that Bermudo was thus put forward as the candidate to, like Mauregatus, prevent the succession of Alfonso II, the son and heir of Fruela I.

Many early twentieth century regimes failed through political instability and / or the interventions of heads of state, notably King Victor Emmanuel III of Italy's failure to back his government when facing the threat posed by Benito Mussolini in 1922, or the support given by King Alfonso XIII of Spain to a prime minister using dictatorial powers in the 1920s.

Thus he assumed he would have their support when he moved against Alfonso II of Naples, especially as the rival claimant was Ferdinand II of Aragon, King of Spain.

Charles VIII expelled Alfonso II of Naples from Naples in 1495, but was soon forced to withdraw due to the support of Ferdinand II of Aragon for his cousin, Alfonso II's son Ferrantino.