Isabella, mother of Katharine of Aragon and one of the Catholic Monarchs, did not easily come to the throne of Castile. Isabella’s older half-brother ruled as Henry IV, known as the Impotent, of Castile. Whether Henry IV was truly impotent became an issue for his daughter and Isabella’s niece, Joanna of Castile. Joanna was Henry IV’s heir until a rebellious faction at court wanted to … Continue reading Isabella and Joanna of Castile: The Fight for the Throne