Agnes’s writings provide a fascinating window on religious life at the court of St. Louis and on the lives of some of the most interesting and powerful men and women of the day. More significantly, they preserve one of the very few female perspectives we have for this period, and, in The Life of Isabelle, offer what is probably the first biography of one woman by another in French. Based on new research into the surviving archives of Longchamp, presents the first English translation of her texts, and the first substantial introduction to her life and work. This critical edition includes both the old French and English versions of the text.