The book "Religion of the Ancient Celts" by the famous British historian John Arnott McCulloch is one of the most authoritative works on the spirituality and faith of the ancient Celtic people. The author examines in detail the religious views, rites, mythology and rituals of the Celts, revealing their relationship to nature, gods and the world in general. In this book, McCulloch uses archaeological and literary sources to reveal the complex system of beliefs and rituals that accompanied Celtic life. It tells about belief in deities, rites of worship, military rituals, relation to sacrifices and events in the life of the community. "Religion of the Ancient Celts" is not only a useful material for the study of ancient history and culture, but also a fascinating book that helps to understand the deep spiritual beliefs of this mysterious people.