King Ferdinand II of Aragon was king in his own right, he did imprison his daughter Joanna to rule Castile. It would be upon his death that Charles V that there was a king of Spain as Charles was heir to both thrones. He held the title Holy Roman Emperor which was a greater title still. Ferdinand II never visited Catherine in England. In this episode he makes comments about her being starved and put into the outer reaches of the Tudor court he was as guilty as was Henry VII he wanted the money she would receive as Arthur's widow and Henry wanted the complete dowry. Catherine was therefore left in England.