Katherine of Aragon, Henry VIII's first bride, has become an icon: the betrayed wife, the revered Queen, the devoted mother, a woman callously cast aside by a selfish husband besotted by his strumpet of a mistress. Her sister, Juana or Castile, wife of Philip of Burgundy and mother of the Holy Roman Emperor Charles V, the most powerful man in Renaissance Europe, is still more of a legend. She is 'Juana the Mad', the wife so passionately in love with her husband that she could not bear to be parted from him even by death, keeping his coffin by her side for year upon year.

They were Sister Queens - the accomplished daughters of Ferdinand and Isabella, the founders of a unified Spain. While their royal birth conferred entry into a world of privilege and plenty, it came at a devastating personal price. Since monarchs played played their parts on an international state, it was inevitable that the formidable Ferdinand and Isabella would send their children abroad as dynastic pawns. Katherine and Juana needed all their courage, resolve and inner strength as they confronted the harsh realities of life in a male-dominated world.