After the failed Fifth Siege of Gibraltar in 1349–50 , which ended Process_end with the death of King Alfonso XI of Castile from bubonic plague , the Kingdom of Castile was preoccupied with the Castilian Civil War and its aftermath .

In the New Year of 1350 , however , bubonic plague – the Black Death – broke out Process_start in the Castilian camp .

The war Hostile_encounter resulted in Causation famine Catastrophe , which was worsened Influence by an outbreak of bubonic plague Catastrophe .