W. Y. Evans-Wentz's "The Fairy-Faith in Celtic Countries" is a monumental, classic work of folklore, ethnography, and comparative religion. First published in 1911, this book is not a collection of fanciful stories, but a serious, scholarly investigation into the deep-rooted conviction held by the peoples of Ireland, Scotland, Wales, the Isle of Man, Cornwall, and Brittany that fairies are a real, non-human, invisible spirit race. Evans-Wentz traveled extensively, meticulously gathering hundreds of firsthand accounts and testimonies from peasants, mystics, and scholars, presenting an unbiased, unfiltered view of this living tradition. The book masterfully connects the modern faith with ancient myths, examining the belief in the Celtic Otherworld, the evolution of the soul, and the parallels between Celtic animism and global spiritual traditions. It offers profound insights into the psychical and psychological significance of the fairy-faith, suggesting a truth far deeper than simple superstition. This definitive text is an indispensable primary source for Celtic studies, comparative mythology, and anyone intrigued by the enduring spiritual power of the unseen world. If you seek the essential, authoritative analysis of the Celtic fairy-faith—from the Tuatha Dé Danann to modern encounters—look no further. Explore the secrets of the Sidhe and unlock the spiritual history of the Celtic nations today!