The concept of a "cult" can be hard to understand for many people, but even more so, cults themselves can just be outright scary.
There's no pinpointing the moment or specific occasion when cults began because the definition of them can vary and be extremely generalized.
In modern culture, though, we can refer back to many examples of cults that have existed even since just the turn of the millennium.
A lot of those examples have even defined modern culture and/or been depicted in films and television that allow us brief and dramatic insight into how they functioned.
Regardless of how well we think we know them, however, cults will always still frighten us on some level, if only because of the things we'll never know about them.
Below, you'll find a condensed list of some of the most terrifying cults that have ever existed, from a story initially shared by Redbook.
Scroll Down for 5 of the Scariest Cult Stories of All Time
The Manson Family is easily the most recognizable cult group of all time.
Lead by Charles Manson, a failed singer/songwriter, the Manson Family started functioning in the late '60s in San Francisco but then moved to Los Angles.
Interestingly, Charles Manson actually lived with Dennis Wilson from the Beach Boys for a short period of time.
Eventually, Manson became obsessed with song "Helter Skelter" by the Beatles, and began to use the term to describe the "race war apocalypse" he believed was coming.
In August of 1969, Manson sent his followers out to a home in Benedict Canyon and ordered them to kill everyone inside.
The next night he did the same thing to a different house.
This killing spree famously claimed the life of actress, and wife of director Roman Polanski, Sharon Tate.
To this day, no official motive has been identified, and that inexplicable violence is the main reason The Manson Family is the scariest cult of all-time.
The Peoples Temple was founded by Jim Jones in the 1950's.
Initially, the belief system he presented was a blend of social equality and Christianity, but, in reality, Jones was mostly phony.
He was reported to use raw chicken parts as props when attempting to convince his followers that he'd healed them of an ailment.
Eventually, Jones moved his group to a commune in Redwood Valley, California, and that's when things began to get more intense.
One day, San Francisco Congressman Leo Ryan attempted to visit the group and Jones' followers, armed with weapons, opened fire on Ryan and his team.
At the same time, inside the temple, Jones commanded his followers to drink a beverage laced with cyanide. This is actually where the term "drinking the Kool-Aid" came from.
That day, a total of 918 people died and it was considered the "largest loss of American civilian life in history" until 9/11.
Marshall Applewhite and Bonnie Nettles founded the Heaven's Gate cult in the 19070s.
Their belief system was very complex and involved spaceships, aliens, and impending "recycling" of Earth.
Nettles dies in 1985 and Applewhite took over the cult at that point. He started telling his followers that a spaceship was following behind the Hale-Bopp comet and that it was going to pick up the Heaven's Gate members.
Applewhite and 38 members of the cult took their own lives by eating applesauce laced with phenobarbital. They were all dressed in matching uniforms and Nike tennis shoes and had $5.75 in their pockets.
To this day, a Heaven's Gate website still exists and is maintained by members of the cult.
The Order of the Solar Temple was founded in 1984, in Switzerland, but they claimed that their roots traced back to the Knights Templar from medieval times.
This particular cult believed that the world would end in the 1990s.
In 1994, things reportedly got violent when the cult's leader Joseph di Mambro ordered to have an infant in Quebec murdered.
Later that year, over 50 Order of the Solar Temple members dies after committing suicide or being murdered, and the group's buildings were burned down.
There were also additional members who committed suicide in 1995 and 1997.
The origin of the Branch Davidians goes back to 1955 when they split off of the Davidian Seventh-Day Adventist belief.
However, it wasn't until 1993 that they become notorious, during the siege of their compound in Waco, Texas.
In 1981, a man named David Koresh assumed leadership of the group at their base, which they called Mount Carmel.
Over the years, many allegations of child abuse emerged against the cult, and so the Bureau of Alcohol, Tobacco,
When they did, a fire-fight broke out and 10 people were killed. Afterward, the FBI seized the compound in a 51-day-long effort that ended with Koresh and 76 other Branch Davidians dead. Before it was over, the cult members set fire to their compound in one final act of defiance.