Have you noticed how a lot of musicians have been covering one eye when posing for photos? Or making some kind of triangle with their hands? Or both? And what’s up with all the occult imagery in videos for Jay Z’s “On to the Next One” and Kanye’s “Power”? Is it just because it looks cool and mysterious?

The conspiracy-minded say there’s something more sinister to it. This is evidence, they say, of a vast, nefarious secret society—the Illuminati—and its plan to institute a New World Order.

Like all of the best conspiracy theories, this one begins with an acorn of truth and ends up in a forest of speculation.

There really was a secret society called the Illuminati, and it really did aspire to transform society by surreptitiously placing its members in positions of influence. The group was formed in 1776 by a young Bavarian professor named Adam Weishaupt. Historian John Roberts described Weishaupt as equal parts lofty idealist and petty narcissist. On one hand, Weishaupt really did want to bring about a less religious, more egalitarian, rational society. On the other, he also really wanted to be head honcho of a spooky secret boy’s club. His Illuminati was designed to scratch both itches. He developed a convoluted hierarchy for his Order, gave recruits codenames (taking Spartacus for himself), and had them infiltrate local branches of the Freemasons and pick off their members.

Over nine years, the Illuminati grew to a few hundred members. But Weishaupt’s personality rubbed some members the wrong way, and they spilled the beans. Rumors about the secret society spread, getting embellished along the way into ever more sordid allegations. By the mid-1780s it had caught the attention of the Bavarian government, which put an end to Weishaupt’s fun by banning Illuminati activity under penalty of death. Weishaupt fled and gave up the secret shenanigans; there’s no evidence that he or anyone else tried to keep the organization going.

That likely would have been the last anyone heard of the Illuminati, if not for the French Revolution, which kicked off a few years later. Searching for an explanation for the unprecedented social upheavals taking place around them, some European authors suggested the Illuminati was pulling the strings. Sensational theories spread around Europe and America alleging that the Illuminati was still operating in secret, more powerful than ever, and that it aimed to overthrow all the governments of Europe.

How did the Illuminati go from orchestrating revolutions to promoting pop stars? The panic of the late 18th century died down quickly. For almost 200 years, the Illuminati took a back seat in conspiracists’ imaginations to other groups like Freemasons, Jews, Catholics, communists, business tycoons, and government bureaucrats.