The Illuminati are a group of comic book superheroes who joined forces and secretly work behind the scenes in Marvel Comics' main shared universe. The Illuminati were established to exist (via story retcon) in their first published appearance in New Avengers #7 (July 2005), written by Brian Michael Bendis. Their history was discussed in the special New Avengers: Illuminati (May 2006). The group was revealed to have been formed very shortly after the Kree-Skrull War, which was depicted in Avengers #89-97 (1971-1972).
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... The Illuminati appear in Planet Hulk ... They are featured as a recorded message telling Hulk that he is too dangerous to be on Earth and apologized for what they had to do ...