| A school of semi-alchemical mysticism that sort of appeared out of nowhere during the late Renaissance, in the form of books and tracts such as Fama Fraternitatis and The Chymical Wedding of Christian Rosenkreuz. Supposedly the first modern magickal order.
The Rosicrucians were also known as the Rose Cross Order; both names relate to the name of the supposed founder, Christian Rosenkreuz (or Christian Rosycross). In fact, the rose and cross are emblems of the female and male in religion and magick. The rosy cross has been a widely-copied symbol since then, and shows up on a lot of rock music albums in the '70s and '80s.
There is a bunch of Egypt-obsessed characters in California who call themselves AMORC -- the Ancient Mystical Order Rosae Crucis, or some such. They advertise in the backs of the same magazines Scientology does. There's no reason to believe they have any connection to the original Rosicrucians.
Aleister Crowley named Rosicrucianism as an ancestor to Thelema.
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