Ferdinand IV of Castile (b. 1285)
Ferdinand IV of Castile (6 December 1285 – 7 September 1312) called the Summoned (el Emplazado), was the king of Castile and León from 1295 until his death.

His upbringing and the custody of his person were entrusted to his mother, Queen María de Molina, while his tutorship was entrusted to his granduncle Henry of Castile the Senator. At that time, and also for the rest of his reign, his mother tried to placate the nobility, confronted her son's enemies, and repeatedly prevented Ferdinand IV from being dethroned. He faced the insubordination of the nobility, led at numerous times by his uncle John of Castile, Lord of Valencia de Campos, and by Juan Núñez II de Lara, who were supported in some occasions by another royal relative, Juan Manuel, Prince of Villena.

Like his predecessors on the throne, Ferdinand IV continued the Reconquista and, although he failed to conquer Algeciras in 1309, he captured the city of Gibraltar that same year, and in 1312 the city of Alcaudete was also conquered. During the Cortes of Valladolid of 1312, he promoted the reform of the administration of justice, and that of all areas of administration, while attempting to strengthen the royal authority to the detriment of the nobility. He died in Jaén on 7 September 1312 aged 26, and his mortal remains are now in the Royal Collegiate Church of Saint Hippolytus.