What are the origins of the illuminati?

Though the term illuminati has been most closely associated with the 18th-century movement of republican free thought in Bavaria, the word has in fact been in use since the late 15th century to refer to various groups. One of the early illuminati groups was the Alumbrados (“Enlightened Ones”), whose movement began in Spain in the 16th century and had ideological roots in gnosticism. A very early leader was María de Santo Domingo, a prophet and mystic who claimed to converse directly with Jesus Christ and the Virgin Mary and was tried under the auspices of the Inquisition. Many Alumbrados later fell victim to the Inquisition, and St. Ignatius of Loyola was charged with having sympathies with the Alumbrado movement. Another early group associated with the illuminati was the Rosicrucians, who came to public attention in the early 16th century but claimed to go back to 1422. Much of what is known about them comes from their earliest extant text, Fama Fraternitatis, first published in 1614, which describes the journey of their founder, Christian Rosencreutz.