From the walled rooms of her prison in Torsedillas, Spain, to the fantasy of her marriage to Philippe the Handsome, a Hapsburg from the Netherlands, Cullen makes a reasonable case against the myth about the daughter of Ferdinand and Isabella of Spain, Juana of Castile - otherwise known as Juana de Loca - in the 15th century. Painted by time and her husband’s determined efforts as a jealous harridan, Juana has borne the weight of that harsh judgment for centuries: far easier to believe the myth than the possibility that Juana was imprisoned for forty-six years in a successful power grab that robbed her of her freedom, children and innocence.

At thirteen, Juana de Castile witnesses the return of Christopher Columbus from his “New World.” Isabella and Ferdinand enjoy unprecedented influence in Europe, their religious fanaticism (the Spanish Inquisition) earning the enthusiastic support of Rome. Third daughter of the monarchs, Juana should never have been in the position to fuel Philippe’s ambitions, but fate dictates otherwise for a newly married young woman who finds unexpected gratification in the arms of her husband. As immature as his virginal bride, Philippe introduces Juana to the pleasures of the marriage bed, and she falls under the spell of the first male to usher her into physical pleasure. Cullen’s efforts on Juana’s behalf in this regard should not be underestimated, for this very passion and willful oblivion will blind Juana to the truth of her precarious situation in time.

The newlyweds are essentially adolescents, politically and emotionally immature. Juana is further hampered by a distant relationship with her mother, Isabella, while Philippe is too easily influenced by the political machinations of his step-grandmother, Margaret of York. Margaret sees potential in the marriage that will thrust Philippe far beyond the expectation of his birth, his future status in Spain appealing to the ego of a handsome young man who has married his way to unexpected power. While Juana is complicit in her own downfall, impossibly in thrall to her husband’s physical prowess, by the time enchantment wears thin, the power has shifted. Philippe and Margaret control the reputation that will define the unfortunate Juana de Loca in history.

There have been rumblings before about the exaggeration of Juana’s madness, but Cullen portrays her protagonist in a sympathetic light made all the more tragic by Juana’s adoration of the man who would literally rob her of everything, including the love and respect of her children. Once Isabella dies, Juana is rendered completely helpless, even her father usurping the crown on her behalf. No man takes pity on this woman, each extracting what best suits their needs. Juana is certainly not the first woman undone by passion, but this 15th-century tale is indeed tragic, especially viewed through history’s perspective.

The attention to period detail and the emotional context of Juana’s tortured existence lends poignancy to this woman’s life, the price of royalty and power too costly, too dear to imagine. I have always doubted the myth and distrusted Philippe, but Cullen brings it all back, immediate and pulsing with passion, betrayal and the profound forfeiture of innocence.