Key Facts
- Duration
- August 1349 – March 1350 (~7 months)
- Castilian army size
- ~20,000 men
- Gibraltar held by Moors since
- 1333
- Notable death
- King Alfonso XI of Castile, died 27 March 1350
- Cause of siege failure
- Outbreak of bubonic plague (Black Death) in Castilian camp
Strategic Narrative Overview
Alfonso XI arrived with approximately 20,000 troops and established a prolonged encampment to the north of Gibraltar, accompanied by his mistress Leonor de Guzmán and their five illegitimate children. The besieging force dug in for a lengthy investment of the fortress. In early 1350, however, the Black Death broke out among the Castilian forces, rapidly spreading through the camp and causing severe losses. Despite the catastrophic outbreak, Alfonso refused to lift the siege or withdraw his army.
01 / The Origins
Gibraltar had been held by the Moorish Emirate of Granada, backed by the Marinid sultanate of Morocco, since 1333. Decades of intermittent conflict between Christian Castile and the Moorish polities had left Gibraltar as an isolated Moorish enclave within Castilian-controlled territory. Its fortifications had been substantially strengthened since 1333, making reconquest difficult. Alfonso XI, having already failed in an earlier attempt, launched a second major siege in August 1349 to reclaim the strategically vital stronghold.
03 / The Outcome
Alfonso XI himself contracted bubonic plague and died on 27 March 1350, becoming the only reigning monarch known to have died of the Black Death. His death brought the siege to an abrupt end, forcing the Castilian army to withdraw. Gibraltar remained in Moorish hands. The king's death triggered a succession crisis in Castile, as his legitimate heir Peter I came to the throne amid tensions with the illegitimate sons of Leonor de Guzmán.
Belligerents & Mobilization Analysis
Side A
1 belligerent
Alfonso XI of Castile.
Side B
1 belligerent
Kinetic Engagement Axis
Scroll horizontally to view full axis. Events plotted relatively.