The term took on its present invidious meaning from a group of five ministers chosen in 1667 by King Charles II of England (Clifford, Arlington, Buckingham, Ashley, and Lauderdale), whose initial letters coincidentally spelled Cabal. This Cabal, never very unified in its members' aims and sympathies, fell apart by 1672; Shaftesbury even became one of Charles II's fiercest opponents. The term, however, continued to hold its general meaning of intrigue and conspiracy. Its usage still carries strong connotations of shadowy corners and occult influence; a cabal is more evil and selective than, say, a faction, which is simply selfish.
During the rise of Usenet, the term gained great coinage as a semi-ironic description of the efforts of people to maintain some order over the chaotic, anarchic Usenet community; see backbone cabal, There is no Cabal. As in this specific case, references to an alleged cabal often fall within the realm of the conspiracy theory.
See also zealot, thug, and assassin for other negative words which came from words describing religious extremism or religious sects.
Cabal is the name of a novel by Clive Barker, which was subsequently made into the movie Nightbreed.
Cabal is also the name of a group on the science fiction television show Enterprise. The Cabal is of a species known as the Suliban. They are the primary villains in the series.
Cabal is also the name of King Arthur's dog.