For six months King Sancho besieged Tarifa by land and sea, his fleet, hired from the Genoese, lying in the waters where the battle of Trafalgar was to be fought. The city at length yielded under stress of famine, but the King feared that he had no resources to enable him to keep it, and intended to dismantle and forsake it, when the Grand Master of the military order of Calatrava offered to undertake the defense with his knights for one year, hoping that some other noble would come forward at the end of that time and take the charge upon himself. He was not mistaken. The noble who made himself responsible for this post of danger was a Leonese knight of high distinction, by name Alonso Perez de Guzman, already called El Bueno, or 'The Good', from the high qualities he had manifested in the service of the late King, Don Alonso VI, by whom he had always stood when the present King, Don Sancho, was in rebellion. The offer was readily accepted, and the whole Guzman family removed to Tarifa, with the exception of the eldest son, who was in the train of the Infant Don Juan, the second son of the late King, who had always taken part with his father against his brother, and on Sancho's accession, continued his enmity, and fled to Portugal. The King of Portugal, however, being requested by Sancho not to permit him to remain there, he proceeded to offer his services to the King of Morocco, Yusuf-ben-Yacoub, for whom he undertook to recover Tarifa, if 5,000 horse were granted to him for the purpose. The force would have been most disproportionate for the attack of such a city as Tarifa, but Don Juan reckoned on means that he had already found efficacious; when he had obtained the surrender of Zamora to his father by threatening to put to death a child of the lady in command of the fortress. Therefore, after summoning Tarifa at the head of his 5,000 Moors, he led forth before the gates the boy who had been confided to his care, and declared that unless the city were yielded instantly, Guzman should behold the death of his own son at his hand! Before, he had had to deal with a weak woman on a question of divided allegiance. It was otherwise here. The point was whether the city should be made over to the enemies of the faith and country, whether the plighted word of a loyal knight should be broken. The boy was held in the grasp of the cruel prince, stretching out his hands and weeping as he saw his father upon the walls. Don Alonso's eyes, we are told, filled with tears as he cast one long, last look at his first-born, whom he might not save except at the expense of his truth and honor.