Minority Moors led by Muhammed IV, Sultan of the emirate of Granada. 's chronicles,
c. 1410 Born on 13 August 1311 in
Salamanca, he was the son of King
Ferdinand IV of Castile and
Constance of Portugal. His father died when Alfonso was one year old. His grandmother,
María de Molina, his mother Constance, his granduncle Infante
John of Castile, son of King
Alfonso X of Castile and uncle Infante
Peter of Castile, son of King
Sancho IV assumed the regency. His mother died first on 18 November 1313, followed by Infantes John and Peter during a military campaign against
Granada in 1319 at the
Disaster of the Vega, which left Dowager Queen María as the only regent until her death on 1 July 1321. Alfonso inherited the throne at a time of instability within the region, decline in populations, reductions in the royal treasury and increasingly ambitious regents caused numerous problems during his young reign. After the death of the Infantes John and Peter in 1319,
Philip (son of Sancho IV and María de Molina, thus brother of Infante Peter),
Juan Manuel (the king's second-degree uncle by virtue of being Ferdinand III's grandson) and
Juan the One-eyed (his second-degree uncle, son of John of Castile who died in 1319) split the kingdom among themselves according to their aspirations for regency, even as it was being looted by Moors and the rebellious nobility. A 14th century chronicle mentioned his appearance as "...King Alfonso was not very tall but well proportioned, and he was rather strong and had fair skin and hair."
Majority His effective reign began in August 1325 when he was sworn in as king as he was proclaimed to have reached the
age of majority in the Cortes of
Valladolid. Following a ritual that took him to
Santiago de Compostela and to the
monastery of Las Huelgas in
Burgos, his self-crowning took place in 1332. As soon as he took the throne, he began working hard to strengthen royal power by dividing his enemies. His early display of ruthless rulership skills included the unhesitant execution of possible opponents. Alfonso XI ordered the assassination of Juan the One-eyed in
Toro in the 1326 feast of All Saints, along with two of the latter's knights, luring the former with promises of reconciliation. He managed to extend the limits of his kingdom to the Strait of Gibraltar after the important victory at the
Battle of Río Salado against the
Marinid dynasty in 1340 and the conquest of
Algeciras in 1344. Once that conflict was resolved, he redirected all his
Reconquista efforts to fighting the Moorish king of Granada. During his reign a political reform in the municipal government took place, with the substitution of the
concejos abiertos by the
regimientos. He fostered the issuance of
cartas pueblas as strategy for the demographic strengthening in the borderland areas. He is variously known among Castilian kings as the Avenger or the Implacable, and as "He of Río Salado." The first two names he earned by the ferocity with which he repressed the disorders caused by the nobles during his long minority; the third by his victory in the
Battle of Río Salado over the last formidable
Marinid invasion of the
Iberian Peninsula in 1340. Alfonso XI never went to the extreme lengths of his son
Peter of Castile, but he could be bloody in his methods. He killed for reasons of state without any form of trial. He openly neglected his wife,
Maria of Portugal, and indulged a scandalous passion for
Eleanor of Guzman, who bore him ten children. Stricken with
plague during the
1349–1350 siege of Gibraltar, Alfonso died in the night of 25–26 March 1350 (some sources put the date wrongfully at 27 March) becoming one of the most prominent victims of the
Black Death. The Castilian forces withdrew from Gibraltar, with some of the defenders coming out to watch. Out of respect, Alfonso's rival
Yusuf I of Granada ordered his army and his commanders in the border regions not to attack the Castilian procession as it traveled with the king's body to Seville. ==Marriage and issue==