20 US presidents who belonged to shadowy secret societies

• A good number of US presidents have belonged to secret societies over the years.

• In fact, a whopping 14 presidents were Freemasons.

• But others belonged to a range of secret societies, from college groups to something called the "Concatenated Order of Hoo-Hoo."

Secret societies always get the ominous treatment in fiction.

Are there any movies with remotely benevolent secret orders? Most fictional secret societies are usually more bogged down with dressing in outdated robes, chanting ominously, doing sacrifices, or hatching nefarious global plots.

So, to the paranoid mind, it probably sounds somewhat startling that 20 out of 45 US presidents have been affiliated with some kind of secret group. Just keep in mind that many of these societies function a bit like social clubs, charitable organizations, and business networks. In many cases, beneath the secret handshakes and mysterious rituals, they're kind of like adult frats (or actual frats, in the case of the college groups on this list).

Here are the presidents who have belonged to a secret society at some point:

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George Washington, Freemasons

That's right. The first president of the US also happened to be rather involved in a secret society.

That's because George Washington was also the country's first ever Masonic president.

In Ron Chernow's "Washington: A Life," he notes that the future president may have been attracted to the Masonic Order's adherence to Enlightenment ideals.

Washington joined the Order of the Freemasons early in his life, entering Fredericksburg Lodge No. 4 at the age of 20, according to Mount Vernon's official website. Washington had lost his older brother Lawrence to tuberculosis only a few months earlier, effectively becoming head of the household.

Washington stayed in touch with his Masonic brothers for the rest of his life.

Masonic influences came into play at Washington's first inauguration. During the ceremony, he swore his oath on a Bible from St. John's Masonic Lodge No. 1 in New York (the book, as Mental Floss reports, was randomly opened to Genesis 49:13: "Zebulun shall dwell at the haven of the sea; and he shall be for an haven of ships; and his border shall be to Zidon").

The first president's Masonic ties followed him his entire life — and beyond. There's even a George Washington Masonic National Memorial, which was dedicated in 1932 and finally completed in 1970.

Thomas Jefferson, F. H. C. Society

Thomas Jefferson may have been a member of the F.H.C. Society at the College of William and Mary, but that doesn't mean he was impressed by the group.

In one 1819 letter, the third US president reflected on his experience in the secret society: "... there existed a society called the F. H. C. society, confined to the number of six students only, of which I was a member, but it had no useful object. Nor do I know whether it now exists."

Ouch.

The initials F.H.C. stood for "Fraternitas, Humanitas, et Cognitio"— Latin for "brotherhood, humanity, and knowledge." However the group became known as the Flat Hat Club, probably a reference to the mortarboards all students wore in those days.

Members identified themselves with a secret handshake, along with a silver badge inscribed with the words "stabilitas et fides" (stability and faith, which is now the motto of William and Mary's campus newspaper). Perks included exclusive parties in the upper rooms of the local taverns, according to "Mr. Jefferson's Women. "

The group pretty much died out when the Revolutionary War interrupted classes. However, the name lived on with William and Mary's student newspaper and the secret society itself re-surged in 1972, under the name the Flat Hat Club.

James Monroe, Freemasons

Mason website The Masonic Trowel lists Monroe as entering the Williamsburg Lodge No. 6 in 1776. At that time he was a 17-year-old student at the College of William and Mary, and heavily involved in anti-Crown activities on campus.

He's recorded as paying dues to the lodge from 1776 to 1780, according to "A Comprehensive Catalog of the Correspondence and Papers of James Monroe: Volume I."

Over the course of those four years, the future fifth president would drop out of college to fight in the Revolution, nearly die after getting shot during the Battle of Trenton, and then return to William and Mary to study law.