In 1973, Raymond Buckland decided to leave Gardnerian Wicca and start a new tradition. He noted the problems in the rigid hierarchy of the Gardnerian and Alexandrian traditions, and aimed to produce a more open and democratic tradition, without violating his vows as a Gardnerian.
He based his Wicca tradition on that information that was publicly available from the Gardnerians as well as what his researches turned up on the pagan practices of pre-Christian Britain/Celtic areas and Saxon lore.
Buckland's book of shadows was titled The Tree. It was publicly available, breaking with past tradition. It was subtitled The Complete Book Of Saxon Witchcraft, but it was a sparse tome, making the assumption that the reader was either well-read in esoteric matters or willing to become that way. This makes it unlike modern Wicca 101 books.
Buckland was willing to admit directly that Seax-Wica was a modern creation based loosely on Saxon practice. Seax-Wica also had a democratically elected High Priest and High Priestess. Seax-Wica also had only one degree, reachable both through initiation by a coven or self-initiation as a solitary practitioner. It was this step which was perhaps the most radical change, leading to many arguments in the Wiccan community over whether or not someone was a "Real Witch".
For more information, look at the books Raymond Buckland's Complete Book of Witchcraft
, The Tree
or these websites: http://www.dmoz.org/Society/Religion_and_Spirituality/Pagan/Wicca/Traditions/desc.html