The book "D. Juana de Portugal (Saint Princess). Biographical sketch" by Gomez, Marques is a fascinating biography of one of the most interesting figures in Portuguese history. This book reveals not only the facts from the life of Princess Joanna, but also her inner essence, spirituality and contribution to the development of the country. The author examines in detail the childhood, youth and adult life of this princess, honored by the holiness of the Church. The book offers the reader new perspectives on the history of Portugal and on the service to the world by the religious personality of Joanna de Portugal.