The book "Encyclopedist of the Age of Darkness: Isidore of Seville" by Ernest Brejo presents the history of the life and activities of the outstanding Spanish archbishop Isidore of Seville, who lived in the 6th century. Isidore was famous for his extensive knowledge in the field of religion, philosophy, science, language and culture. He became known as a scientist, writer and teacher who made a significant contribution to the development of medieval education. The book tells about the creative path of Isidore of Seville, his work on the creation of the encyclopedia "Etymology", which became one of the important sources of knowledge in medieval times. The author, Ernest Breho, examines in detail the life and activities of the great encyclopedist, shedding light on the period of history when the preservation of knowledge and knowledge of the world were extremely important tasks for society. This book is not only an in-depth biography of Isidore of Seville, but also a study of the religious, cultural and intellectual aspects of the time, which makes it interesting not only for historians and specialists, but also for the general public who appreciate the knowledge and heritage of past eras.