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In page Alfonso XI of Castile:

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He is variously known among Castilian kings as the Avenger or the Implacable, and as "He of Río Salado." The first two names he earned by the ferocity with which he repressed the disorders caused by the nobles during his long minority; the third by his victory in the Battle of Río Salado over the last formidable Marinid invasion of the Iberian Peninsula in 1340.[citation needed]