These days, secret societies are hardly secret. You can drive by a Masonic lodge today and see people walking in and out, paying no heed to keeping their identity or involvement in the movement a secret. Similarly, Yale University’s “secret” Skull and Bones society is not at all a secret, and indeed, your Yale tour guide will gladly point out their “secret” meeting place when your tour walks past.

However, centuries ago, secret societies were, well, secret, for a variety of reasons. As the question-and-answer column The Straight Dope reported, the Masons probably began as a guild and kept things secret in order to keep outsiders from learning the masonry trade. Later, religious persecution led to organizations meeting in secret; as The Vintage News reports, the Catholic Church was keen to keep Catholics out of freemasonry because it accepted members who believed in God, regardless of whether they were Catholic or Protestant, and such free thinking would not do at the time.

However, one Catholic group formed their own secret society, took a dog as their mascot, and even required members to behave like dogs in order to gain admission to meetings.

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