So great were her power and influence over the soldiery that Catherine de' Medici, her bitter enemy, desiring to bring her into her power, or, at least, to conciliate her, planned a marriage between Jeanne's son and Marguerite of Valois--sister of Charles IX. When the suggestion that the marriage should take place came from the king of France, Jeanne d'Albret suspected an ambush; with the determination to supervise personally all arrangements for the nuptials, she set out for the French court. Venerated by the Protestants, and hated but admired by the Catholics, she had become celebrated throughout Europe for her beauty, intelligence, and strength of mind; thus, her arrival at Paris created a sensation.
She was so scandalized at the luxury and bold debauchery at court that she decided to give up the marriage; she had detected the intrigues and falsity of both the king and Catherine, and had a foreboding of evil. She wrote to her son Henry:
"Your betrothed is beautiful, very circumspect and graceful, but brought up in the worst company that ever existed (for I do not see a single one who is not infected by it) ... I would not for anything have you come here to live; this is why I desire you to marry and withdraw yourself and your wife from this corruption which (bad as I supposed it to be) I find still worse than I thought. Here, it is not the men who invite the women, but the women who invite the men. If you were here, you could not escape contamination without a great grace from God."
In the meantime, Catherine, undecided whether to strike immediately or to wait, was redoubling her kindness and courtesy and her affectionate overtures; her enemies were in her hands. Although Jeanne suspected that Catherine was capable of every perfidy, she at times believed that her suspicions were unjust or exaggerated. The situation between these two great women was indeed a dramatic one: both were tactful, powerful, experienced in war and diplomacy; both were mothers with children for whose future they sought to provide. Jeanne's hesitancy, however, was fatal; physically exhausted from suffering and sorrow, worry and excitement, she suddenly died, in the midst of her preparations for the marriage. While it is not absolutely certain that her death was due to poison, subsequent events lead strongly to the belief that Catherine was instrumental in causing it--that, probably, being but the first act toward the awful catastrophe she was planning.