Freemasonry has attracted much speculation — and even a few conspiracy theories — since its inception.

Numerous United States presidents have been drawn to the all-male secret society throughout history.

Some presidents, like Harry Truman, say they were able to hone their leadership abilities through their participation in Masonry.

Others, like Andrew Jackson, attracted criticism for belonging to what was viewed as a strange and elitist group.

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Almost a third of the US presidents have been Freemasons.

It's a statistic that sounds straight out of a conspiracy theorist's fever dream (or "National Treasure," at the very least).

Masonic lodges essentially function as combination social clubs, secret societies, and charitable organizations. The fraternal organization has been around since at least the 1700s, likely arising from early modern organizations of stonemasons. Masons themselves trace their roots back to the construction of King Solomon's temple in biblical times.

Today, there are several offshoots of Freemasonry, but the branch that most people would recognize requires that members be men and profess belief in the existence of a deity. Conversations about politics and religion are banned, and a sacred text must be displayed in each lodge.

Candidates must get through three degrees of the craft in order to become Freemasons. First, they are "initiated" as apprentices, then "passed" to the level of fellowcraft, and finally "raised" as full Masons (if the members of the lodge vote them in).

Since the society is ostensibly mysterious and said to partake in ancient rituals, public perceptions about Masons tend to range from fascination to fear. In fact, the first ever third party in US political history ran on the platform of taking down Freemasonry.

Recently, a statue of prominent Freemason — and Confederate general — Albert Pike was toppled and set on fire by protesters on Juneteenth. NBC Washington reports that President Donald Trump personally requested that Pike's statue be returned and put back up in the DC park. Pike was a member of the Scottish Rite branch of Freemasonry; according to Kyley Schultz at WUSA9, he was instrumental in growing the branch.

"That Albert Pike statue is up here only because the Freemasons erected it, and Albert Pike was a Freemason. To the credit of the Freemasons, they joined me in wanting the statue to be taken down and I give them all due credit to that," Congresswoman Holmes Norton told WUSA 9.

So, what drew a grand total of 14 chief executives (15 if you count LBJ, who was initiated but never raised) to become Masons?

Let's take a look at some of their Masonic experiences to find out: