Alfonso XI ascended the throne of Castile and León in 1312, inheriting a kingdom fractured by competing regents and political instability. His eventual assertion of majority power in 1325 transformed the monarchy, characterized by ruthless consolidation of control and the expansion of Castilian borders through significant military campaigns against the Marinid dynasty and the kingdom of Granada.
Minority and Political Turbulence
Born on 13 August 1311, the son of Ferdinand IV and Constance of Portugal became king while still an infant. His early years were defined by power struggles among his grandmother María de Molina, his mother, and various ambitious infantes. The deaths of key regents in 1319 at the Disaster of the Vega left the government in a state of chaos, with rival factions looting the treasury and exploiting the lack of central authority.
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Upon reaching the age of majority in 1325 at the Cortes of Valladolid, Alfonso initiated a period of aggressive governance. He neutralized potential rivals through extrajudicial means, most notably ordering the assassination of Juan the One-eyed in 1326. He further restructured municipal administration by replacing open councils with regimientos and utilized the issuance of cartas pueblas to fortify the demographic standing of border regions.
Military Expansion and the Black Death
The king earned the moniker el Justiciero for his harsh suppression of noble dissent and his military achievements. His victory at the 1340 Battle of Río Salado halted the Marinid invasion of the Iberian Peninsula, and his 1344 conquest of Algeciras significantly extended his kingdom's reach. During his final military effort, a siege of Gibraltar, Alfonso contracted the plague, dying on 26 March 1350.
Personal Life and Succession
His marriage to Maria of Portugal in 1328 followed the annulment of his union with Constanza Manuel. While Maria bore him his successor, Peter of Castile, Alfonso maintained a long-term relationship with Eleanor of Guzmán. This union produced ten children, including the future King Henry II of Castile, creating a complex dynastic legacy that persisted long after his death.
Fast facts
- Born: 13 August 1311, Salamanca
- Died: 26 March 1350, La Línea de la Concepción
- Reign: 1312–1350
- Burial site: Iglesia de San Hipólito, Córdoba
- Nicknames: The Avenger, The Implacable, He of Río Salado
- Religion: Catholicism
Questions readers ask
How did Alfonso XI die?
He died of the plague during a military siege of Gibraltar in 1350.
What political changes did he implement?
He centralized power by replacing open municipal councils with regimientos and incentivized population settlement in border areas.
