Walter Yeeling Evans-Wentz (February 2, 1878 – July 17, 1965) was an anthropologist and writer. As a teenager, he became interested in the teaching of Theosophy. While at Stanford University, he studied with William James and W. B. Yeats. After receiving his B.A. and M.A. from Stanford, he went to Jesus College, Oxford, to study Celtic mythology and folklore. At that time he added his mother’s Welsh surname and was thereafter known as Evans-Wentz. This book, The Fairy-Faith in Celtic Countries is based on his doctoral thesis at Oxford. It is an extensive survey of the phenomenon of the Celtic belief in fairies from various perspectives, including folklore, history, anthropology, archaeology, and psychology. He later went on to become one of the leading authorities on Tibetan Buddhism.