The book "Correspondence of Madame, duchess Palatine, mother of the regent; Marie-Adelaide de Savoy, duchess of Burgundy; and Madame de Maintenon in the context of Saint-Cyr" provides an opportunity to review the historical letters of prominent women of the French royal court of the 17th century. This book collects and interprets the correspondence of three influential ladies of the time who were active in correspondence. Their letters reveal the thoughts, feelings, and values that were relevant to the aristocratic society of France during the Ancien Regime era. In addition, the book highlights the role of the Saint-Cyr educational institution, founded by Madame de Maintenon, in the education of girls and the formation of their secular and spiritual culture.