Good, Christian American families were whipped into a hysteria over a shadowy, secretive — and possibly even satanic — cabal subverting our nation’s democracy, conspiring against justice, and performing bizarre, blasphemous rituals.

This may sound like a modern, paranoid movement on social media, but it’s actually describing a 200-year-old conspiracy theory in the U.S. that alleged that men in the growing Freemasonry fraternity were engaged in a nefarious plot to exert unchecked control over the republic. The Anti-Masonry movement grew to become the first “third party” in the country’s history, permanently altering American politics during a transformative political realignment that would see new parties, ideals, and democratization of the U.S. system.

The spread of Anti-Masonry and its attendant conspiracy theories were aided by the simultaneous religious revivals sweeping across the states, and the movement’s transference into the political sphere met with other opponents of Andrew Jackson. But an important aspect of this conspiracy theory has often been overlooked: it began in reaction to an actual conspiracy.

No other modern historian has spent as much time digging into the history of Anti-Masonry as Kathleen Smith Kutolowski. Born and raised in a small town in Genessee County, New York, she collected otherwise untouched Masonic data from the region, offering a more complete picture of 1820s New York and demystifying the period of supposed hysteria.

Kutolowski’s father belonged to a Masonic lodge. When she began writing her dissertation on the general political development of the area in the 19th century, she says, “I kept running into Masons as political leaders, right down to candidates for county coroner.” She analyzed the records of Genessee and nearby counties and found that Masons were not necessarily the upper-class elites that many had thought; they came from a variety of backgrounds, economic statuses, and denominations.

This was in line with her discovery that there were many more Masonic lodges in Western New York than anyone else had cared to document.“Masonry was a more widespread phenomenon than people understand, and they dominated political office,” she says.

In the 1820s, Freemasonry enjoyed explosive growth in cities, towns, and even small villages in the Northeast. Tens of thousands of Masons had established hundreds of lodges in states like New York, Massachusetts, and Connecticut, and they held “influential civic positions out of proportion to their numbers,” according to Kutolowski’s research. Many of the founding fathers, including George Washington and Benjamin Franklin, had been Masons. In New York especially, Masons held power. But the popular movement against them arose because of the ways they wielded it, particularly in Genessee County in 1826.