Fernando Sánchez de Castro
Fernando Sánchez de Castro (1241–1275) was an Aragonese infante (royal prince), crusader and rebel leader. Fernando was an illegitimate son of King James I of Aragon by his mistress Blanca, daughter of Sancho de Antillón. Their relationship can be dated to 1241, when James gave her the castle of Castro. Fernando later took the title of . In April 1261, Fernando and were sent to Naples as ambassadors to King Manfred of Sicily. As a result of this embassy, James's heir, the infante Peter, was married to Manfred's daughter, Constance. Fernando was a witness to their wedding on 13 June 1262 in Montpellier. At the of 1264 in Zaragoza, Fernando clashed with his father over the extension of the tax on livestock from Catalonia to Aragon. When the Aragonese nobility withdrew from the cortes, Fernando sided with them. He thereby gained enduring popularity with the nobility of Aragon and married a daughter of . Despite these clashes, Fernando remained a favourite of his father. Fernando took part in the crusade to the Holy Land launched by his father on 4 September 1269. When his father diverted the fleet to Aigues-Mortes after a storm and opted to abandon the enterprise, Fernando