France and England, particularly during the early medieval period. The opening of this work presents a dedication to a noble figure, Monseigneur Armand-Thomas Hue, which sets an authoritative tone and indicates the book's serious scholarly intention. Following this dedication, the preface discusses the significance of historical sources, such as compiled legislation from Norman and Gascon regions, for understanding past legal practices and customs. It emphasizes that without knowledge of these origins, the study of laws and customs would lack depth, potentially leading to the loss of vital historical knowledge. The author plans to elucidate these connections further through analysis of legal texts and commentary, inviting readers into a detailed inquiry of ancient laws that governed society in both France and England. (This is an automatically generated summary.)