Diego López V de Haro, nicknamed el Intruso ( 1250 – 1310), was a Castilian noble of the House of Haro and held the title of the Lord of Biscay which he took from the pretender to the title, John of Castile.
He further served in the capacity of Mayordomo mayor del rey and the Alférez del rey of Ferdinand IV of Castile. He was a major benefactor of the city of Bilbao, where he expanded the local fishing village and granted it the power to maintain its customs market free of any Portazgo (royal tribute) answerable only to the authority of the Lord of Biscay.
Family origins
Diego López was the son of Diego López III de Haro and his wife, Constanza de Bearne. He eventually inherited the title of Lord of Biscay from his father after his sister and the usurper to the title, John of Castile. His paternal grandparents were Lope Díaz II de Haro, Lord of Biscay, and his wife, Urraca Alfonso de León, the illegitimate daughter of Alfonso IX of León. His maternal grandparents were Guillermo II de Bearne, the Viscount of Bearne, and his wife, Garsenda of Provence.
Amongst his siblings were Lope Díaz III de Haro, Lord of Biscay, Teresa de Haro, wife of Juan Núñez I de Lara, head of the House of Lara, and of Sancha Díaz de Haro. He was the great grandson of the king, Alfonso IX of León.
Biography During the youth of Fernando IV de Castilla (1295–1301)
Diego López' exact date of birth is unknown, but it most likely occurred sometime around the year 1250. In 1282, he married the infanta Violant of Castile, daughter of King Alfonso X of Castile.
On 25 April 1295, after the death of King Sancho IV of Castile (who the Haro family had fought to overthrow), Diego López took advantage of the instability in the court of the young King Ferdinand IV of Castile and took power over the Lordship of Biscay which rightfully belonged to his niece, María Díaz I de Haro.
The incessant fighting against the Castilian crown, led primarily by the following infantes; John of Castile, an enemy of the Haro family who claimed the throne as the heir to his brother, Sancho IV of Castile, Infante Henry of Castile, son of Ferdinand III of Castile and uncle of the young king Ferdinand IV, who claimed guardianship over the king. This was exacerbated by the claims of the infantes of Cerda, Ferdinand de la Cerda and Alfonso de la Cerda, who were supported by France, Aragón, and their grandmother, Queen Violant of Aragon, widow of Alfonso X of Castile. Still further, problems also arose with the Kingdom of Aragon, Portugal, and France, who all tried to take advantage of the instability that plagued the contemporary Kingdom of Castile. Finally, internal Castilian players such as Diego López V de Haro, Nuño González de Lara, and Juan Núñez II de Lara, amongst others, sowed confusion and anarchy throughout the kingdom.
During the summer of 1295, after the Cortes of Valladolid of the same year, Diego López was confirmed in his illegitimate possession of the Lordship over Biscay, turned over by the pretender to both Biscay and the Castilian throne, infante John of Castile. During this time, John also temporarily accepted Ferdinand IV as his sovereign and he regained his previous possessions and titles.
On 15 June 1300, Diego López V de Haro converted the fishing village of Bilbao into a town under the authority of the Lords of Biscay.
During the Cortes of Valladolid in 1300, the infante John of Castile officially renounced his pretendership to the throne despite being proclaimed king of León in 1296. He took an oath of fealty ti Ferdinand IV and his successors on 26 June 1300. The same year, María Díaz I de Haro together with her husband (the same infante Juan), as compensation for renouncing her claim over the Lordship of Biscay, received title over Mansilla, Paredes de Nava, Medina de Rioseco, Castronuño, and Cabreros. A short while later, Maria de Molina, and the infantes Henry and John, accompanied by Diego López V de Haro, laid siege to Almazán, but lifted the siege due to opposition from the infante Henry.
During the adolescence of Fernando IV de Castilla (1301–1310)
In November 1301, Diego López was in the court of the city of Burgos when the papal bull of Pope Boniface VIII made public the marriage of María de Molina (mother of Ferdinand IV) and the dead Sancho IV of Castile. This recognition by the pope, coupled with the coming of age of Ferdinand IV of Castile instantly made the claims to the throne of John of Castile, Henry of Castile, Alfonso de la Cerda, and Ferdinand de la Cerda much less plausible as they had thereby lost one of their principal claims to the throne. Going forward, the crown of Castile and León was much more secure.
The infante Henry, upset over the legitimization of Ferdinand IV by the pope, forged an alliance against the head of the House of Lara, Juan Núñez II de Lara in an effort to alienate Ferdinand IV from his mother, María de Molina. The likewise embittered magnate, John of Castile started his own faction together with Juan Núñez II de Lara in an effort to reclaim the Lordship of Biscay for his wife, María Díaz I de Haro. Later in 1301, the king placated Henry with titles over Atienza and San Esteban de Gormaz as compensation.
In 1302, the rivalry between these two factions became clear with infante Henry, Maria de Molina and Diego Lopez on one side and the infante John of Castile and Juan Núñez II de Lara on the other. The infante Henry threatened the Queen with a declaration of war against her and Ferdinand IV if she did not acquiesce to his demands. This coincided with a fall from grace of Maria de Molina as the contemporary magnates attempted to lessen the grip of power she had maintained over the king. In the final months of 1302, the queen was in Valladolid where she agreed to placate the members of the nobility who threatened her with war against King Ferdinand IV who spent Christmas with John of Castile and Juan Núñez II de Lara in the Kingdom of León.
In 1303, there was a meeting between the King Denis of Portugal and Ferdinand IV where in Ferdinand obtained the return of various territories. The split between the two aforementioned factions continued. In May of that year, celebrations over the success of the meeting (which neither Diego Lopez, Maria de Molina, or Henry of Castile participated in) were held in Badajoz. Further agreement was reached by Ferdinand IV and Denis of Portugal to obtain Portugal's assistance against the opposing faction. Diego Lopez' faction met in Roa with Juan Manuel, Prince of Villena, giving the latter orders to travel to the Kingdom of Aragon and to enlist his support against Ferdinand IV. The group agreed to reunite on the Day of John the Baptist in the municipality of Ariza. Henry of Castile later conveyed this message to Maria de Molina who was in Valladolid at the time. Henry's plan was for Alfonso de la Cerda to become King of León, marrying the infanta Isabel de Castilla y de Molina, daughter of Maria de Molina and sister of Ferdinand IV. At the same time, the infante Pedro de Castilla y Molina, brother of Ferdinand IV, was to be named the King of Castile, marrying one of the daughters of James II of Aragon. Henry claimed that his intention was to foster peace in the kingdom and eliminate the influence of the infante John of Castile and that of Juan Núñez II de Lara.
This plan, which proposed the breakup of the Kingdoms of Castile and León and the forced or obliged resignation of Fernando IV, was rejected by the queen Maria de Molina who refused to meet the rebel faction in Ariza. At the same time, the queen was asked by King Ferdinand IV to help foster a peace between him and the rebel faction. The queen traveled to Ariza where instead of supporting the rebel cause, she pleaded with the group to remember their oaths of fealty to the king and to return to his service causing many of the rebels to abandon the cause of infante Henry and Diego Lopez. This move, which weeded out many of the more moderate rebels, served only to cement the hardline base who vowed to wage war against the king, demanding further that the Kingdoms of Murcia and Jaén be turned over to Alfonso de la Cerda. It was during this time that the infante Henry of Castile became deathly ill and retired to his villa at Roa. Fearing that Henry's possessions would revert to Diego Lopez and Juan Manuel upon his death as was his wish, the queen plotted with Henry's confessor to convince him to leave all his possessions to the crown. This move inevitably failed and Diego Lopez, together with Juan Manuel inherited all his possessions when Henry died on 8 August 1303. He was sepulchered at the now destroyed Monasterio de San Francisco de Valladolid.
In November 1303, the king asked the queen for her support in an effort to end the infighting between infante John of Castile, Lord of Valencia de Campos and Diego Lopez for control over the Lordship of Biscay which at this time was under the full control of Diego Lopez. The queen agreed to help her son and the relationship of mother and son was restored when she succeeded in reaching an agreement with the infante John.
In winter of 1304, the king was in the area of Carrión de los Condes when the infante John once again claimed for his wife the lordship of Biscay together with the continued support of Juan Núñez II de Lara. The king attempted to offer her title over Paredes de Nava and Villalón de Campos as compensation, but this was refused by the infante John. The king then drafted a lopsided deal where Diego Lopez V would turn over his titles over Tordehumos, Íscar and Santa Olalla. He would also be made to give up his possessions in Cuéllar, Córdoba, Murcia, Valdetorio, and his title as Señorío de Valdecorneja. In return for this, Diego would be able to keep Lordship of Biscay, Orduña-Urduña, Balmaseda, las Encartaciones, and Durango. Understandably, the infante John accepted these terms and the king called Diego Lopez to Carrión de los Condes to cement the deal. Not surprisingly, Diego Lopez V refused these demands and threatened an all out rebellion against his rule.
The king, who was at the time preparing for the Treaty of Torrellas, from which Diego Lopez was excluded, promised the infante John that he would receive Biscay after all and that Juan Núñez II de Lara would get La Bureba. He further stated that both could divvy up the territories currently belonging to Diego Lopez in La Rioja if the two could resolve the diplomatic crisis that was ongoing with Aragon.
In April 1304, the infante John commenced negotiations with the Kingdom of Aragon to resolve demands made by Alfonso de la Cerda and disputes held by the Aragon. In the meantime, the king confiscated the territories of Diego Lopez V and of Juan Alfonso de Haro, Señor de los Cameros and divided them up amongst his supporters. After this bold move, many of the rebels came back under the fold of the king.
In winter of 1305, Diego Lopez once again refused the kings demands that he hand over Biscay at Guadalajara.
Fighting over possession over the Lordship of Biscay (1305–1307)
In 1305, Diego Lopez V was called to present himself in the courts of Medina del Campo which took place that year, to respond to the demands of the king.
At the court, María Díaz I de Haro, Diego's niece and wife of the infante John, demanded the return of her rightful property, the title of Lord of Biscay, a title which Diego had taken in the unrest that surrounded King Ferdinand IV of Castile's younger days on the throne. While the infante John and Maria were presenting their case to the court, Diego Lopez, together with three hundred of his knights arrived at the court and Diego Lopez announced his refusal to give up his title, citing a deal struck in the year 1300 where his niece had renounced her claim. Diego Lopez V left the court without waiting for its final decision and began drafting a proposal soliciting aid from the pope.