On January 2 , 1492 , Muhammad XII of Granada ( King Boabdil ) surrendered Surrendering the Emirate of Granada , the city of Granada , and the Alhambra palace to the Castilian forces Hostile_encounter .

The frontier between Granada and the Castilian lands of Andalusia was in a constant state Statement of flux , `` neither in peace nor in war . ''

King Henry IV of Castile died Death in December 1474 , setting off the War Hostile_encounter of the Castilian Succession between Henry 's daughter Joanna la Beltraneja and Henry 's half-sister Isabella .

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 .

A Castilian fleet put Placing to sea and inflicted Causation a major defeat Conquering on the Moors in the Strait of Gibraltar .

The city remained Presence under Castilian occupation Control for two weeks , during which they captured Conquering 3,000 residents and took Conquering them as slaves .

According to historian Ibn Khaldun , when the Marinid dynasty took Conquering control over Salé from the Almohad Caliphate , Yacoub ben Abdellah le Mérinide rebelled Hostile_encounter against his uncle Abu Yusuf Yaqub ibn Abd Al-Haqq , and sought the assistance Assistance of King Alfonso X. Ruy López de Mendoza , Admiral of Castile formed Coming_to_be an armada to assist Assistance with Castilian crusades on the North African coast .

On 2 Shawwal , Castilian warriors landed in Salé and took Conquering the opportunity to perform Action the largest massacre Killing in the history of the city .

He ordered Request that all Castilian soldiers were to be killed Killing , but some were able to escape Escaping the attack after ransacking houses , and looting and burning shops .

The siege began Process_start inauspiciously with a disastrous landing Self_motion by Castilian forces on the west side of Gibraltar , before developing Coming_to_be into a stalemate in which neither side had the strength Cause_change_of_strength to capture Gibraltar , nor to break out Destroying or lift Body_movement the siege .

A series of Moorish defeats and reverses Escaping had left Causation Gibraltar as a Moorish-held enclave within Castilian territory .

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

Several attempts were made to reconquer Conquering Iberian Navarre immediately following the Castilian invasion .

Charles had been raised Cause_change_of_position_on_a_scale in the Netherlands with little knowledge of Castilian .

These factors resulted in Causation mistrust between the new king and the Castilian social elites , who could see the threat to their power and status .

April 23 is now celebrated Social_event as Castile and León Day , and the incident is often referred to in Castilian nationalism .