Discordianism

Discordianism is a religion based upon the book Principia Discordia.

Historical
The book was written by Greg Hill with Kerry Wendell Thornley in 1963, the two working under the pseudonyms Malaclypse the Younger and Omar Khayyam Ravenhurst.

The Principia Discordia, if read literally, encourages the worship of the Greek goddess Eris, known in Latin as Discordia, the goddess of disorder, or archetypes and ideals associated with her. Depending on the version of Discordianism, Eris might be considered the goddess exclusively of disorder or the goddess of disorder and chaos. Both views are supported by the Principia Discordia. The Principia Discordia holds three core principles: the Aneristic (order), the Eristic (disorder), and the notion that both are mere illusions. Due to these principles, a Discordian believes there is no distinction between order and disorder, since they are both man-made conceptual divisions of the pure element of chaos. An argument presented by the text is that it is only by rejecting these principles that you can truly perceive reality as it is, chaos.

Conspiratorial
Discordians are often said to work in opposition to the Illuminati,

Some sources, including The Illuminatus! Trilogy, claim the disorganized Discordians are in opposition to the highly organized Illuminati.