Editing Ferdinand IV of Castile (section)

==Conflicts over the possession of the Lordship of Biscay (1305–1307)==
[[File:House of Haro COA.svg|200px|thumb|right|Coat of arms of the House of Haro. [[María I Díaz de Haro]], daughter of Lope Diaz III de Haro and wife of John of Castile, claimed during the reign of Ferdinand IV the possession of the Lordship of Biscay, which was in the hands of her uncle, [[Diego López V de Haro]].]]
In 1305 [[Diego López V de Haro]] was called to appear in the ''Cortes'' of Medina del Campo, although he didn't come but after being summoned several times, to respond to the demands of his niece [[María I Díaz de Haro]], who claimed, using the influence of her husband [[John of Castile, Lord of Valencia de Campos|John of Castile]], the possession of the [[Lordship of Biscay]].

In the absence of the Lord of Biscay, John of Castile filed a lawsuit against him before Ferdinand IV, and alleged that he can prove that the Lordship of Biscay was illegally occupied by Sancho IV of Castile, which is why it was now in the hands of Diego López V de Haro, uncle of his wife. However, while John of Castile presented the evidence to the King's representatives, Diego López V de Haro arrived, accompanied by 300 knights. The Lord of Biscay refused to renounce to his domains, arguing that John of Castile and his wife had renounced to their rights in a solemn oath in 1300.

Failing to reach an agreement, due to the arguments presented by both parties, Diego López V de Haro returned to Biscay, although the ''Cortes'' de Medina del Campo had not yet finished until mid-June 1305. In mid-1305, the court was in the city of [[Burgos]], and while Diego López V de Haro proposed to appeal to the Pope, due to the solemn oath of resignation to the Lordship of Biscay made John of Castile and his wife in 1300, Ferdinand IV offered to María I Díaz de Haro the possession of several cities of the Lordship of Biscay, among them [[San Sebastián]], [[Salvatierra/Agurain|Salvatierra]], [[Hondarribia|Fuenterrabia]] and [[Gipuzkoa|Guipúzcoa]], but she refused, advised by Juan Núñez II de Lara (who was distanced from with her husband) and despite the pressures of John of Castile. Shortly thereafter, John of Castile and Diego López V de Haro signed a truce, valid for two years, during which the King was confident that the Lord of Biscay would break his alliance with Juan Núñez II de Lara. Later, during Christmas of 1305, Ferdinand IV met with Diego López V de Haro in [[Valladolid]], but the Lord of Biscay was accompanied by Juan Núñez II de Lara, who was forced by the King (because he was estranged from him) to leave the city, because he wished to break the alliance between him and Diego López V de Haro, although the monarch did not succeed, since the Lord of Biscay was convinced that John of Castile would not cease in his claims.

At the beginning of 1306, [[Lope Díaz de Haro (d. 1322)|Lope Díaz de Haro]], son and heir of Diego López V de Haro, was also estranged from Juan Núñez II de Lara and tried to persuade his father to accept the solution proposed by Ferdinand IV. That same year, the King gave the position of First ''Majordomo'' to Lope Díaz de Haro; shortly after, the Lord of Biscay had a meeting with the King, but again caused his anger because arrived accompanied by Juan Núñez II de Lara. During the meeting, Diego López V de Haro tried to reconcile Juan Núñez II de Lara with the sovereign, while the latter tried that the Lord of Biscay broke his relations with his ally. Persuaded by Juan Núñez II de Lara, Diego López V de Haro left without the King's consent, while ambassadors arrived from the [[Kingdom of France]], requesting an alliance between both countries, and also asking the hand of ''Infanta'' [[Isabella of Castile, Queen of Aragon|Isabella of Castile]], sister of Fernando IV.

In April 1306, John of Castile, despite the opposition of the Dowager Queen, induced Ferdinand IV to declare war to [[Juan Núñez II de Lara]], knowing that Diego López V de Haro would defend him, and advised the monarch besiege [[Aranda de Duero]], where Juan Núñez II de Lara was, who, in view of the situation, broke his oath of vassalage to the King. After a camp battle, Juan Núñez II de Lara managed to escape from the siege to which Aranda de Duero was intended to be subjected, and met Diego López V de Haro and his son, and agreed to declare the war on Ferdinand IV separately in their respective domains. The royal troops demanded concessions from Ferdinand IV, who had to grant them even though they were not diligent in making war, and so the King ordered John of Castile to enter into negotiations with Diego López V de Haro and his supporters, to which he agreed, because his vassals didn't supported the war.
[[File:Don Diego López de Haro V.jpg|250px|thumb|left|Statue that represents [[Diego López V de Haro]], Lord of Biscay, work of [[Mariano Benlliure]].]]
Negotiations didn't begin, and the war continued, although John of Castile advised the monarch to sign the peace if this was viable. Ferdinand IV asked the intervention of his mother, who, after negotiations with the rebels through [[Alonso Pérez de Guzmán]], succeeded in arrange a meeting with them in [[Pancorbo]]. In the meeting was agreed that the three rebellious magnates granted castles as hostages to the King, who in exchange from their homage as vassals, promised to respect their properties and pay their troops; however, the agreement didn't satisfy John of Castile, who renewed his claim over the Lordship of Biscay in the name of his wife, while Ferdinand IV, with the purpose of pleasing John of Castile, took the [[merindad]] of [[Galicia (Spain)|Galicia]] from his brother the ''Infante'' [[Philip of Castile, Lord of Cabrera and Ribera|Philip of Castile]], and granted to Diego García de Toledo, private of John of Castile.

Ferdinand IV, still anxious to please John of Castile, sent Alonso Pérez de Guzmán and Juan Núñez II de Lara to talk with Diego López V de Haro, who refused to cede the Lordship of Biscay to John of Castile and his wife, [[María I Díaz de Haro]]. When John of Castile learned of this, he summoned [[Juan Manuel, Prince of Villena|Juan Manuel of Villena]] and his vassals to support him in his pretensions, while the King and his mother talk with Juan Núñez II de Lara to persuade Diego López V de Haro to return the Lordship of Biscay. In September 1306 the King had a meeting with Diego López V de Haro in [[Burgos]]. Ferdinand IV proposed that Diego López V de Haro could retain the Lordship of Biscay during his lifetime, but after his death the succession should pass to María I Díaz de Haro, with the exception of the cities of [[Orduña-Urduña|Orduña]] and [[Balmaseda|Valmaseda]], which should be granted to Lope Díaz de Haro, son of Diego López V de Haro. However, the proposal wasn't accepted by Diego López V de Haro, and in view of his obstinacy, the monarch again tried to end his alliance with Juan Núñez II de Lara. Shortly afterwards, the Lord of Biscay again appealed to the Pope.

At the beginning of 1307, while the King, his mother, and John of Castile were going to [[Valladolid]], they learned that [[Pope Clement V]] recognized the validity of the oath taken by John of Castile and his wife in 1300 about their resignation over the Lordship of Biscay; in consequence, John of Castile was forced to accept it or respond to the lawsuit brought against him by Diego López V de Haro. In February 1307, another attempt was made to resolve the dispute over the Lordship of Biscay, who repeat the terms of the meeting of Burgos in September 1306, but with the addition that, besides Orduña and Valmaseda, Lope Díaz de Haro would also receive the cities Miranda and Villalba de Losa from the King. However, again the agreement wasn't accepted by the Lord of Biscay. Soon after, the ''Cortes'' were summoned in the city of Valladolid.

In the ''Cortes'' de Valladolid in 1307, when María de Molina saw that the ''ricoshombres'', led by John of Castile, protested against the measures taken by the King's privates, she tried, in order to please John of Castile, to put a definitive end over the possession of the Lordship of Biscay. For this, the Dowager Queen counted on the collaboration of her half-sister Juana Alfonso de Molina, who persuaded her daughter María I Díaz de Haro to accept the agreement proposed by the King in February 1307. Diego López V de Haro and his son Lope Díaz de Haro agreed to sign the agreement, who followed the terms of the previous meetings of September 1306 and February 1307: María I Díaz de Haro should succeed her uncle after his death and Lope Díaz de Haro received the cities of Orduña, Valmaseda, Miranda and Villalba de Losa.

Once the agreement about the possession of the Lordship of Biscay became known, Juan Núñez II de Lara felt despised by both the King and his mother, and he suddenly left the ''Cortes'' before they had finalized. For this reason, Ferdinand IV granted the position of First ''Majordomo'' to Diego López V de Haro, which caused that John of Castile left the court, warning the King that he wouldn't count with his help until the governors of the castles of Diego López V de Haro paid homage to his wife María I Díaz de Haro. However, shortly afterwards they met in [[Lerma, Province of Burgos|Lerma]], where are already stay María I Díaz de Haro, John of Castile, Juan Núñez II de Lara, Diego López V de Haro, and Lope Díaz de Haro, and was agreed that the Biscay nobility would pay homage to María I Díaz de Haro as heiress and future Lady of Biscay, and the same oath was done in the cities and castle that would receive Lope Díaz de Haro.