1. El comienzo
2. Los reyes legítimos de las tierras de la Corona de Aragón
3. La Cámara de Barcelona
4. La creación de la Casa de Aragón-Ayerbe
5. 1412-1454
   5.1. Aragon-Ayerbe: 1412 – 1454
6. 1454-1853
7. La Casa de Ayerbe y el pacto de 1853
8. 1853 – 1860
9. 1860 – 1965

The beginning

The Kingdom of Aragon was one of the small Christian states which arose in the Iberian peninsula following the gradual expulsion of the Moors, who had held sway in the area in the wake of their conquest of the old Visigothic realm of Spain in the eighth century. It lay in the northeast of the peninsula and the earliest ruler of which we take note in this brief history was Aznar Galindez, Count of Aragon (which included the territories of Urgell, Cerdanya and Conflent) for twenty years from 809 AD. The first of his successors to be regarded as King of Aragon was Ramiro I (1035-1063), an illegitimate son of Sancho the Great, King of Navarre who ruled in Pamplona 1000-1035 and who from 1028 was also King of Castile.

Ramiro I was succeeded by his son Sancho Ramirez, who had already been introduced into the government of the very unstable kingdom while his father engaged in military activities. After a pilgrimage to Rome Sancho returned with a fervent devotion, and thus began the particular close links between the Crown of Aragon and the Holy See, breaking with family tradition by baptising his firstborn Pedro (Peter). For thirty years he consolidated and expanded his territories by conquest. He died from an arrow wound while besieging Moorish occupied Huesca in 1094.

Pedro I inherited an effective conglomeration of lands, albeit all under the rule of his father. He welded them into a recognisable kingdom with common government, rights and responsibilities. He was a supreme administrator of his fractious barons. He followed his father’s example as a favoured son of the Church and also made his pilgrimage to Rome.

Alfonso I «the Battler» succeeded his father in 1104. While he also was a great religious reformer and proponent of the religious Orders within his lands, his fame which went well beyond his frontiers arises mainly from his military conquests of such important cities as Fraga and Lerida, though in his pursuit of the enemy he traversed Valencia and reached the frontier with Granada.

When he died in 1134 he was childless and bequeathed his kingdom to the crusading military Orders, the Templars and the Hospitallers, but his Will was set aside by the magnates of the realm in favour of the late king’s brother Ramiro, a monk who was given papal dispensation to set aside his religious vows in order to continue the dynasty. As Ramiro II he married Agnes of Aquitaine and, after fathering Petronila the much wanted heir, he retired once more to his monastery in 1137.

In early childhood Petronila (ob. 1173) married Raymond Berengar IV, Count of Barcelona (ob. 1162), thus uniting the crowns of the two states in one much stronger kingdom with access to the sea. Henceforth the ruling dynasty of Aragon was styled the House of Barcelona.

Their son Alfonso II (1157-1196) was the first Aragonese monarch who was also Count of Barcelona. He unified the disparate territories under his crown, civic institutions were set up in the towns and these incorporated into a hierarchy of government. Despite his marriage to an infanta of Castile, hostilities with the neighbouring Christian kingdom were a constant feature of his reign. Himself a noted lyrical poet, Alfonso II was a great patron of troubadors. By his Will Alfonso set a sorry precedent when he sought to bequeath his territories beyond the Pyrenees to a second son.

His son Pedro II (1178-1213), known as «The Catholic», was imbued with a profound religious devotion by his mother and saw his role as a knight champion of Christianity very much in that context. His generosity to the chivalric orders was prodigious. The Templars of Montpellier arranged for the marriage of the heiress of that city to Pedro who despite a marked attraction to women took a total adversion to his legitimate spouse, to the extent of refusing to consummate the marriage, and eventually seeking to divorce her. The marriage was in fact consummated as a result of trickery by the queen in an episode regarded by their ensuing son as a miracle.

Pedro made his way to Rome in 1204 to be solemnly crowned there by Innocent III. Meanwhile in Languedoc the Albigenisan heresy sprang up with the active support and participation of certain of the local rulers among whom Pedro had solemn allies and vassals. In order to defend them and in spite of his own orthodox beliefs, Pedro met the Catholic armies from northern France under Simon de Montfort before the castle of Muret and despite his own numerical superiority he lost the battle and his own life in the course of it. The infant son from the miracle of Montpellier, the great-grandson of Raymond and Petronila, who succeeded to the throne in 1213, was James I (King also in due course of Majorca and Valencia, Count of Barcelona and Urgell, Lord of Montpellier) known to history as «the Conqueror».

The legitimate kings of the lands of the crown of Aragon

James I was five years old at his accession on the death in battle of his father Peter II. He occupied the throne until his death in 1276 and during his long and brilliant reign laid the foundations of the Aragonese Empire or, to give it its correct title, the Lands of the Crown of Aragon.

In 1228 James wrested Majorca from the Moors and ten years later did likewise with Valencia. By these conquests he received the sobriquet of «James the Conqueror».

His first marriage was to Eleanor of Castile, by whom he had a son Alfonso, who died without progeny in 1260. The King’s union with Eleanor was dissolved in 1229 and in 1235 James wed Yolande of Hungary. This marriage produced seven children, of whom three were sons. In due course the eldest became King Peter III of Aragon, the second James was granted the Kingdom of Majorca (with its capital in Perpignan) in 1286, the third son Sancho became Archbishop of Toledo and was murdered in 1275. Of the daughters the eldest married King Alfonso X of Castile, while the second became the wife of King Philip III of France from which union the Royal House of France traces its descent from James the Conqueror of Aragon.

Queen Yolande died in 1251. In the meantime the King had formed a relationship with Doña Teresa Gil de Vidaure, by whom he had had two sons, James Baron of Xerica, born c1255, and Peter Baron of Ayerbe and Lord of Paternó in 1260. After the birth of Peter the King married Teresa and had their two sons legitimised. Then, by his Will dated 21st August 1261, he provided that they should take precedence in right of succession to the throne over any of his daughters and their descendents born of his union with Yolande. In 1260 the Pope recognised the marriage of James and Teresa and gave his consent to the known intention of the King, which in due time became the first formal law of succession to the Lands of the Crown of Aragon. The House of Xerica became extinct in 1309, but that of Ayerbe continues to this day.

The House of Barcelona

Peter III, son of James the Conqueror, known as «the Great», came to the throne in 1276. Six years later the people of Sicily revolted against the French who under Charles II of Anjou had invaded their country. In a bloody affair known as the Sicilian Vespers, the French were massacred and the local nobility invited the Aragonese monarch to accept the Crown. Peter III of Aragon accordingly also became King of Sicily.

Peter III reigned until 1285 when he was succeeded by his son Alfonso III, who ruled until his death in 1291.

At this point the Crown of Aragon passed to another son of Peter III, James II of Aragon. In 1296 the new king granted the crown of Sicily to his younger brother Frederick, at which stage that monarchy became for a number of years separate from Aragon.

James II was followed in 1327 by his son Alfonso IV, who reigned until 1336 when his son Peter IV («the Ceremonious» or «the Cruel») ascended the throne.

In 1375 Peter attacked and defeated the last King of Majorca and reunited the crown of that kingdom with that of Aragon. In 1381 Peter IV secured the homage of the Duchy of Athens which had been under Catalan rule since the reign of his kinsman Frederick II of Sicily (1296-1337) whose Catalan mercenaries had captured the area.

Peter was followed on his death in 1387 by his son John I, who died without male heirs in 1395, to be succeeded by his brother Martin I, «the Humane». The new monarch’s son, also Martin, had become King of Sicily in 1390 by virtue of his descent from Eleanor of Sicily, the third wife of Peter IV (the male line of the Sicilian kings having died out).

Martin of Sicily expired without heir in 1409 and his father took the throne of the island in addition to his existing sovereignty of Aragon. A year later he also died and with this the surviving eldest line of the House of Barcelona became represented by James Count of Urgell, younger son of Alfonso IV. He did not in the event succeed to the Throne of the Lands of Aragon, as was his undoubted right.

The inception of the House of Aragon-Ayerbe

As mentioned before, James I the Conqueror had long concluded that at his death the sovereignty over the Lands of the Crown of Aragon would be divided between the sons he had by his second wife, Yolanda of Hungary, and thus by his Will he separated the Kingdom of Aragon (comprising Aragon proper, Catalonia and Valencia) under Peter III from the Kingdom of Majorca (comprising the Balearic Islands with Perpignan, the Roussillon and Montpellier) under James II. His sons by his third wife, Teresa Gil de Vidaure, James and Peter were made Lords of Xerica in Valencia and Ayerbe in Aragon as well being given various other cities and territorial holdings throughout the lands of the Crown, sufficient to make them independent and vastly significant magnates within the Kingdom.

Peter first Lord of Ayerbe married Aldonza of Cervera who brought in her dowry extensive lands in Catalonia.

Peter had a son Michael who in turn sired a boy, Giovanni the Elder born in 1347 and who in 1398 became Vicar General of the Kingdom of Sicily. Giovanni married Sibilla Spadafora and from that union descends unbroken the male line of the House of Paternó.

Individual members of the House of Paternó regularly held the highest offices in the land including Archbishop of Palermo, Viceroy, Ambassador to the Pope and Lord in Waiting to successive Kings of the Two Sicilies and the latter gave full recognition to the Family’s particular status including the Order of St. Agatha.


When Martin I «the Humane» died in 1410, leaving no provision regarding his successor, a fierce struggle broke out between no fewer than six claimants. The nearest in the male line was James Count of Urgell and thus the legitimate heir. However, a large body of nobles and other magnates supported the claims of Ferdinand of Antequera, son of Eleanora (ob.1382) daughter of Peter IV (1336-1387) by her marriage with John I of Castile. The other three claimants in the male line were descendants of James II’s younger son Peter of Ribagorza (died 1387).

The controversy raged for two years. Finally it was agreed that the issue should be settled by a commission of nine members, three from each of the kingdoms of Aragon, Catalonia and Valencia. The members were to consider the claims of each of the contenders and decide by simple majority vote which of them should succeed to the throne. While the commission was considering its verdict, Castilian troops commanded by Ferdinand of Antequera met the supporters of the Count of Urgell in a pitched battle at Murviedro and put them to rout.

On 24th June 1412 the commission decided that Ferdinand of Antequera should succeed to the Crown of the Lands of Aragon. Six members voted for Ferdinand, one (who was himself a substitute) abstained on the grounds that he had neither the qualifications nor the experience to decide so difficult a question, while the two remaining judges voted for succession through heirs in the male line – these being James of Urgell and Alfonso Duke of Gandia, a grandson of Peter of Ribagorza.

The event is known as the Compromise of Caspe after the town in which the commission had held its meetings. The decision was not well received by the unsuccessful claimants.


The Count of Urgell refused to accept the decision, was arrested and imprisoned for life and died without heir in 1433. The Duke of Gandia died without heir in 1454. At this point the Will of James I again became operative, directing that his descendants in the male line from his third wife, namely the House of Ayerbe, were to take precedence over any descendants in the female line, including Ferdinand of Antequera.

The latter’s grandson Ferdinand the Catholic eventually succeeded to the throne of Aragon in 1479. By his marriage to Isabella the heiress of Castile in 1469 the kingdoms were united and modern Spain was born.

Meanwhile in Sicily the House of Ayerbe threw off various branches which characteristically intermarried and some became extinct. Finally, in 1853 the last Prince of Cassano in the direct male line died without heir. He had been regarded as the undisputed Head of Ayerbe, which position thereupon became a matter of debate. Therefore a family conclave of the cadet branch of Paternó’s called in Palermo at the express request of King Ferdinand II, the Bourbon King of the Two Sicilies who regarded the House of Ayerbe as royal and sovereign and therefore wished to have the matter resolved.

As will be described further below, the decision of the conclave, set down in the Family Pact of 1853, was that the Head of the House of Ayerbe was Don Mario, son of Don Giovanni the younger brother of the Duke of Carcaci by his marriage with Donna Eleonora Princess of Emmanuel who alone claimed descent from King James I the Conqueror through the lineage of both his father and his mother. This decision was carried unanimously by the conclave was held in the palace of the Marquises of Spedalotto, a cadet branch of the Paternó, and ratified by the King. The Family Pact stipulates that thenceforth the succession would pass through the descendants of Don Mario. The reigning Head of the House, Don Francesco I, is the great-great-grandson of Don Mario.

Aragon-Ayerbe: 1412 – 1454

We may thus regard Ferdinand of Antequera (in fact a member of the Castilian House of Trastamara) as a usurping monarch by means of a military coup and the line which led from him and his wife, Leonor of Albuquerque, to the parent of Catherine of Aragon (consort of Henry VIII of England) as one of unlawful succession.

When James Count of Urgell died in captivity in 1433, the legitimate line passed to the Duke of Gandia who died without heir in 1454. At this date the operative document became the Will of James I the Conqueror, which had clearly said that his legitimised male descendants by Teresa Gil de Vidaure were to take precedence in the succession over those in a female line born of Yolanda of Hungary. The lawful succession to the thrones of the Lands of the Crown of Aragon thus passed in 1454 to the House of Ayerbe.

The legality of the Caspe decision remains extremely dubious and is disputed in the lands of the Crown of Aragon to this day. It has to be borne in mind that in the Middle Ages there was no statute law to regulate the succession to the Aragonese throne. It was customary for the king to designate who was to follow him, either during his lifetime or by his will. Apart from this it was the accepted practice that the Crown should pass to the nearest male in the male line of the Royal House.


Teresa Gil de Vidaure was the third wife of James the Conqueror who in his Will of 21st August 1261 recognised their two sons James and Peter, born before the marriage but subsequently legitimised, and allowed the succession to pass through them should the senior lines fail, which they did when the Count or Urgell and the Duke of Gandia died without heirs in 1433 and 1454, respectively.

The honoured custom since time immemorial was and remains that, provided that there is no specific debellatio (that is, renunciation of sovereign rights), the jus maiestatis inheres forever in the person of the lawful head of the family in accordance with the will of the particular family under consideration. This principle is now incorporated in international law.

Thus, when the Duke of Gandia died in 1454 – his line leading from James I of Xerica (c1255-1280) the elder legitimised son of the Conqueror, being already extinct since 1409 – without a direct heir, as mentioned above, the Headship of the House of Aragon and de jure kingship of the Lands of the Crown of Aragon passed to a descendant of James of Ayerbe, the elder son of Peter of Ayerbe (born 1260) the Conqueror’s younger legitimated son. This nobleman, Sancho, was in fact the great-great-grandson of Peter. His grandson, Alfonso, became Count of Simari in 1519, and Alfonso’s grandson, Alfonso III, became Marquis of Grotteria. In turn Caspar VI, Alfonso III’s great-great-great grandson, became the first Prince of Cassano. These great nobles were de jure kings of the Lands of the Crowns of Aragon until their line became extinct with the death before 1851 of Joseph the last Prince of Cassano.

The succession thence passed to the cadet branch of the House of Ayerbe, descended from Peter, the younger son of Peter, the second of the legitimised sons of King James the Conqueror and Teresa Gil de Vidaure.

At the end of the 18th Century, Ignazio Vincenzo Prince of Biscari, one of the foremost intellectuals in Europe in his day, made a truly regal visit to the Balearic Islands, to discover for himself the kingdom of his ancestors and see what light he could shed on the chivalric traditions of his House. The notes he made during this visit were the basis of the researches of Francesco Duke of Caraci in the succeeding century.

In the 19th Century a wave of mediaeval revivalism swept through Europe from which Sicily was by no means exempt. The then Duke of Carcaci, a prominent intellectual notably researched the historical order of chivalry in his family’s gift, a study which even merited mention in his eventual funeral eulogy.

Through all the vicissitudes suffered by the island of Sicily during successive occupations it was only during the rule of the House of Aragon that the independent kingdom had its own resident monarch. One after another ruling foreign dynasties simply despoiled the country for ther own ends. While the House of Paternó remained loyal servants, for the most part, of the regnant house of the day, the well being of Sicily was always uppermost in their aims. On their part the Kings of the Two Sicilies lost no opportunity to confirm the Serene status of the princely house.

The House of Ayerbe and the pact of 1853

Over the centuries the descent had thrown off numerous branches, many of which have intermarried. Thus, when the last Prince of Cassano died, it was not clear who precisely held the dynastic right to the jus maiestatis of the Lands of the Crown of Aragon and it became urgently necessary that the question be answered.

A family conclave, on the initiative of the Duke of Carcaci Don Francesco Paternó Castello e Sammartino, was called on 14th June 1853, and held in Palermo in the palace of the Marchese di Spedalotto, head of one of the more senior branches of the family. After a review of the relevant evidence and a wide-ranging discussion, it was the finding of the conclave that the royal rights, which had been the subject of the debate, should be confirmed as belonging to Don Mario, son of the Duke of Carcaci’s younger brother Don Giovanni and his wife Donna Eleonora Guttadauro of Emmanuel Riburdone, the heiress of the House of Guttadauro. This conclusion which had in fact already received the assent of King Ferdinand II of the Two Sicilies (in whose realm they resided), subject to ratification by the conclave, was reached on the recognition that Don Mario alone had the royal blood of Aragon in his veins from two sources, through the separate descents of both his mother and his father from King James the Conqueror.

A family pact was then signed, registered on 16 June 1853 and sealed in the Chamber of Seals and Royal Registers of the Kingdom of the Two Sicilies. It was decreed that during the minority of Don Mario, his father Don Giovanni should be Regent.

1853 – 1860

The sealing of the family pact was but one of a series of events following the death of the last Prince of Cassano which determined and confirmed the dynastic rights of the House of Paternó Castello Guttadauro. The final endorsement came on 2nd February 1860 when the Royal Commission for Titles of Nobility recommended to the new king Francis II that a petition by the Most Excellent Lord Don Mario Paternó Castello Guttadauro of the Dukes of Carcaci be granted. The petition was that the Prince should receive all confirmation of the Sovereign’s assent for those «chivalrous distinctions» which he wished to bestow. On 11th February 1860 the king approved the recommendation of the Royal Commission and directed the Secretary of State for Sicilian Affairs to give effect to his approval.

1860 – 1965

The designated Regent, Don Giovanni, worked vigorously to assert the dynastic rights of the family. In doing so he was crowning the work of his elder brother the great Duke of Carcaci who had died in 1854, having spent his life establishing his family’s Royal dynastic rights and regulating the succession.

The principal vehicle used by the Regent was the Military Order of the Collar of Saint Agatha of Paternó taking full advantage of the recognition granted by successive kings of the Two Sicilies, Don Giovanni proceeded to recruit to the Order the flower of the nobility of Sicily. In 1859 the Royal Order of San Salvador of Aragon, which had been founded in 1118 by Alfonso I, had been revived and in 1861 the Order of the Royal Balearic Crown was established.

The year 1861 was a fateful one. Don Giovanni the Regent died and Don Mario I, by then twenty-three years old, assumed full responsibility for the rights of his House. The Bourbon monarchy of the Two Sicilies was overthrown and its kingdoms were incorporated into that of the newly created Italy under the sovereignty of Victor Emmanuel II of Sardinia of the House of Savoy. Thereafter Don Mario maintained a policy of neutrality favouring neither the intruding House of Savoy nor the deposed Bourbons.

Two of his three sons predeceased Don Mario and his third son Don Enrico succeeded his father in 1906. Don Enrico died in 1908 without issue and by the Will of Don Mario the succession passed to Donna Eleanora Angela Maria, sister of Don Enrico, and to the issue of her marriage to her cousin Don Roberto Paternó Castello, brother of the tenth Duke of Carcaci. In 1913 Donna Eleanora bore a son, Don Francesco Mario II for whom his father acted as Regent until he attained his majority in 1934.

Don Francesco Mario II was a colourful, indeed flamboyant, character who vigorously promoted the dynastic rights of his family – not always, be it said, diplomatically. In November 1965, due to painful illness and thus being unable to exercise his full powers, he decided to associate his son the Infante Don Roberto (born in 1937) with himself in the government of the Royal House. In October 1962 in the ancestral church of Santa Maria di Gesù Catania, Don Roberto had married Noble Maria of the Counts Fattori. On 28th November 1965 Don Francesco Mario issued a Decree conferring on Don Roberto the title of Prince of Gerona and formally sharing with him his sovereign and magisterial powers.

Intellectual members of the family maintained its best traditions of researching their royal origins. The institution of a Republic in Italy after the Second World War led to the introduction of legislation which sought to curtail if not abolish Orders of Chivalry unless those of the republican state itself and to outlaw nobiliary titles unless pre-existent and added to the family surname. Don Francesco Mario II and his successors knew themselves to be a fons honorum and thus in that specific regard the subject of international and not national law. Therefore they continued to administer their chivalric patrimony as well as to make judicious grants of noble titles. Inevitably they and the recipients of these honours were prosecuted (18, 19) in the courts of law but in every instance justice was awarded to the House of Paternó. Independent specialist academics concurred(17, 20, 21) with the judgements of the courts.

For a look at some of the primary sources, please see the archive