The "History of Wicca" is something everyone wonders about sooner or later, and it is a hotly debated subject in the Pagan world. Traditionalists argue about “fluffy bunny” Wiccans, Witches argue about Wiccans calling themselves Witches, and it is a horrid mess! I have tons of books, been to thousands, if not tens of thousands, of websites and I've even talked to some few people. All of these sources have mostly agreed with each other on the basics and such, but, then you get to (insert drum roll here)…Wicca’s history.
From my point of view, Wicca has very little history in and of itself. It was started in Britain by Gerald Gardner, circa 1954. That's it folks, it’s not an ancient religion. It’s based on an ancient religion (or two or three).
When the laws against Witchcraft were repealed in Britain in 1951, Gerald Gardner wrote his book "Witchcraft Today". This is a non-fictional account of "Modern Witchcraft". Hence, we have Wicca. Wicca is a modern version of Witchcraft. If you look in the "What is Wicca/Witchcraft" section of this site, I explain Wicca as being "…based on pre-Christian, northern European Pagan beliefs in a (fertility) Goddess and a horned God (her Consort)....". This is also what I (roughly) understand Witchcraft to be. I wasn't around before Christianity, so I cannot say for certain what Traditional Witchcraft was (and, I have to tell you, I don’t think anyone can.) Educated guess, but, I don't believe that it’s all that different from Wicca. After all, the apple doesn't fall that far from the tree.
Therefore, in mine eyes anyway, the history of Witchcraft is the history of Wicca - somewhat. Wicca itself was essentially created in 1954, when Gerald Gardner came out of the (broom) closet. Wiccans have 47 years (from this writing) of history. I do, however, believe that we have at least a partial right to claim the history of Witchcraft as our own. Although, what history people want to claim is beyond me. The Burning Times? What people don't seem to understand is that most of those people that were killed were not even witches, or pagans. I won't get specific, because I don't have any proper references, but if you look it up (reliable sources here people, reliable sources), you'll see what I mean.
One quick thing and I'll let you go on your merry way. I've seen somewhere a statement that Wicca "just is" Celtic. One certainly wishes that were true. Being 1/2 Irish, I'd love to know I'd picked a religion that tied in with my roots. Alas, Wicca in itself is not Celtic. There are, however, quite a few Celtic Traditions, re-constructionists, Druids, etc.. I'll get into that later...or you'll be here all night.