Jim Jones (1931 / 1978) was an American cult leader and 'preacher' who founded the Peoples Temple, a movement (under a 'venere' of Christianity) of socialism / Marxism and racial equality. Originally from Indiana, Jones moved his group to California before establishing a remote, abusive jungle commune in Jonestown, Guyana.
On November 18, 1978, Jones orchestrated the mass murder-suicide of over 900 followers, a defining event in the perception of cults.
  The Movement ("Peoples Temple"): Founded in 1955, the group originally emphasized racial integration and social justice, attracting thousands of members by the 1970s, particularly in San Francisco.
  Ideology: Jones preached a blend of communist ideology and religious, apostolic socialism, aiming to create a utopian community free from capitalist and racial oppression.
  The Move to Guyana: Facing increasing media scrutiny in California regarding abuse allegations, Jones moved his followers to a compound in Jonestown, Guyana, in the mid-1970s, creating a restricted, paranoid atmosphere.
  The November 18, 1978 Events: After U.S. Congressman Leo Ryan visited to investigate abuse claims, Jones ordered the murder of Ryan at a nearby airstrip. Immediately after, 909 members died from drinking cyanide-laced punch (or were forced to do so) in what Jones called "revolutionary suicide".
The Jonestown tragedy resulted in the largest single loss of American civilian life in a deliberate act prior to 9/11 ....... indeed, the ideology of Jim Jones is alive and well today.