One of the most well known figures from the 60's is Charles Manson. This cult would kill for an apocalyptic cause. Manson didn't kill by his own hand, but used his group to kill. A master manipulator and textbook dark personality.

Notes:

https://en.wikipedia.org/wiki/Charles_Manson

https://en.wikipedia.org/wiki/Manson_Family

Interviews:

https://youtu.be/S3W8GtwInYg?si=ptgcu0Z9zbChG6xQ

https://youtu.be/YxxH6xm_ZVg?si=nJC3f1atVPaL_K9Q