In the thread “Innocent words with disturbing etymologies”, someone mentioned the term “Assassin”–which has as its origin a group of medieval Isma’lis who used terrorist-style killing of enemies by individual murderers as a tactic; they were so good at this, that the pejorative term used to describe them “hashishin”, or eaters of the drg hashish - became our word for any sort of individualized murderer for a cause.
However, of course, the group is still around - led by the Aga Khan:
Despite their medieval infamy, they are nowadays comparatively harmless and inoffensive.
Another example of this sort of thing is the Anabaptists–nowadays, they are as inoffensive a sect as you could find–but it was not always so:
I read the thread title as “Modern-Day Groups with Sinister Organs”, which brought to mind Procol Harum (although they weren’t the first thing I thought of).
They are mostly faded and forgotten, but a lot of fraternal organizations had questionable roots, organizing one immigrant or minority population or another for better jobs, wages, treatment or just to beat hell out of that other immigrant population. A number of those organized in the northern states from 1900-1930 or so were openly Socialist or Communist societies. German Turnverein groups still exist in many cities, and they had their… questionable eras with strong ties to National Socialism.
And, of course, there’s the Noble Order of Red Men, organized to celebrate the wisdom and strength of Injuns… and open, until quite recently, only to white males.
Well, not sinister, but the Seventh Day Adventists are the modern descendants of the Millerite Church that believed that the End of the World was upon us. In 1833
To explain further, the most common Anabaptists you’re likely to see in the US are Mennonites and Amish. They completely rejected the the violence of the other Anabaptists and are pacifists.
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For an interesting history, the Knights Hospitaller, a medieval order used to maintain Christian control of the Holy Land, are still around as an international aid organization.
Not exactly “sinister” to the free-wheeling libertines of the Dope, but:
Global silverware giant Oneida Limited grew out of the Oneida Community, a utopian religious community most famous for advocating “free love,” seeing “exclusive wedlock as an unhealthy institution,” and so on.