The Battle of Río Salado, occurring in 1340, was a pivotal confrontation during the Reconquista, where the Christian kingdoms of Portugal and Castile united against a Muslim invasion led by the forces of the Kingdom of Granada and their allies from North Africa. The battle unfolded near the Río Salado river in southern Spain, a strategic point that became essential for controlling the flow of military reinforcements and resources. Both sides were eager to assert dominance in a period characterized by intense territorial conflicts between Christian and Muslim powers on the Iberian Peninsula.

The coalition commanded by Portuguese King Afonso IV and Castilian King Alfonso XI demonstrated innovative military tactics, incorporating disciplined infantry, cavalry charges, and archery formations. The Muslim forces, composed of well-trained troops from Granada and North Africa, aimed to re-establish control over territories previously lost to the Christian kingdoms. The outcome of the battle was heavily influenced by the strategic positioning and coordination between the allied forces, which led to a decisive victory for the coalition. The battle's aftermath solidified the power of the Christian kingdoms and hindered Muslim expansion in the region.

The Battle of Río Salado was not only significant for its immediate military outcomes but also for its broader implications in the Reconquista. It represented a critical juncture in the centuries-long campaign to reclaim the Iberian Peninsula from Muslim rule. The victory reinforced Christian claims over southern Spain and marked a turning point in the power dynamics of the region. The success at Río Salado emboldened future campaigns and set the stage for further conquests, leading to the eventual conclusion of the Reconquista in 1492.