The Triumph of the Moon: A History of Modern Pagan Witchcraft by Ronald Hutton is by far the best academic read on the history of the occult, the craft, and the last two centuries of pagan thinkers like French Occult philosopher Eliphas Zahed Levi, who was a major influence on 20th century occultists. In it, Hutton traces the mythology and roots to the last century of pagan philosophy to the Freemasons who trace their roots to medieval guilds in Scotland.
Wiccapedia: A Modern-Day White Witch’s Guide is a cute favorite for baby witches who wants a short snippet of the craft and life lived magically. I highly suggest it for anyone who is either interested in it out of curiousity (maybe for writers who need good material to work with) or for anyone who wants a simple reference guide that can lead you down rabbit holes into lighter and lighter more magical places.
The Meaning of Witchcraft by Gerald Gardner is considered an essential reference for any witch’s library. Gardner who is the modern day founder of Wicca, he popularized the neopagan movement starting in the 1950’s. This work is considered the Bible of Wicca and an essential work for understanding the craft on a more advanced level. For all travel aficionados, you can visit Gardner’s Museum of Wicca on the Isle of Manx, one of the six Celtic Nations. It is a small island in the Irish sea situated between Ireland and Britain. Manx is a revived Gaelic language in its infancy stages of being spoken again as living language.