The Marquis de Sade, infamous for his obscene writing and his cruelty to women, nonetheless lived a life dominated by them - his charismatic mother, iron-willed mother-in-law, and his wife. A wife who, despite her husband's peccadilloes, and although their marriage was arranged in order for their families to combine financial and social capital, loved him devotedly for thirty years, through betrayal, imprisonment, and national turmoil. This biography reveals how Renee-Pelagie de Montreuil, Marquise de Sade, endured the chaos caused by her frenetically dissolute husband with grace, and how she carved out her own independence in an era when women were entitled to little of their own.