This is a uniquely American idiom. “Kool-Aid” is a well-known brand of drink-mix sold in the United States, available in a range of flavors. Just open a packet, mix the powder with water and ice, and you get yourself a sugary flavored drink. Most Americans, going back a few generations, are familiar with its jolly mascot, the Kool-Aid Man (an anthropomorphized pitcher).

However, the backstory for the idiom isn’t about Kool-Aid as a product in and of itself, but its unfortunate association with a particularly horrific mass murder-suicide that happened in November 1978, notoriously known as “The Jonestown Massacre“.

Rev.Jim Jones, an American cult leader (although the title ‘reverend’ is usually associated with Christianity, what Jones preached was basically Marxist socialism), was able to persuade his followers to move and live in a “socialist paradise” on an isolated piece of land in the middle of the jungle in Guyana, a tiny South American country. After a few years, words leaked that some cult members felt they were held there against their will and things weren’t so rosy in ‘paradise’. They wanted to return to the United States. A U.S. Congressman along with several members of the press flew to Guyana to try to intervene and bring these ‘defectors’ home. Long story short: as this delegation and a tiny group of defectors boarded a small plane on an airstrip for the return trip to America, armed guards of the cult opened fire and killed several people, including Congressman Leo Ryan, three journalists and some of the defectors.

But the deadly violence didn’t end there.

Back in Jonestown, the increasingly paranoid Jones rallied his remaining followers in a giant meeting. Here’s where ‘Kool-Aid’ is forever (and unfairly) linked to this horrific incident: Jones and his aides had prepared a giant tub filled with a grape-flavored drink laced with a toxic cocktail of cyanide and sedatives.

In this rally Jones successfully convinced his followers to commit suicide. He ordered mothers to give the sweet deadly concoction to their babies and children first before drinking it themselves. The poison took only minutes to work.

Over 900 people died in this mass suicide, over 300 of them were children. Jones committed suicide by shooting himself in the head.

As authorities took photo evidence in the aftermath, it showed that most of the drink mix used to flavor the poison was of another brand (not so well-known), together with just few packets of Kool-Aid. But it was the Kool-Aid brand that Americans identified with and remembered most.

Since then, the phrase “to drink the Kool-Aid” means “to blindly follow/obey” someone or a movement/philosophy/ideology, or it refers to someone who has forsaken healthy independent thinking process and instead follows ‘groupthink’ unquestioningly. It’s almost always used in the negative sense.

“Don’t drink the Kool-Aid!” is a warning to not blindly follow or obey.

The actual Kool-Aid drink mix – colorful, sweet and harmless – is still widely sold in the United States.