Retrocon

Retroactive continuity, or retcon for short, is a literary device in which established facts in a fictional work are adjusted, ignored, or contradicted by a subsequently published work which breaks continuity with the former.

There are various motivations for applying retroactive continuity, including:

Retcons are used by authors to increase their creative freedom, on the assumption that the changes are unimportant to the audience compared to the new story which can be told. For instance, by retroactively setting a prior story in a parallel universe, departed popular characters can be reintroduced. More subtly, a minor plot point might be retroactively expunged (for instance, the heroine leaving home without any food), removing an obstacle to further storytelling (that she should be getting hungry).

Retcons are common in pulp fiction, and especially in comic books published by long-established publishers such as DC and Marvel. The long history of popular titles and the number of writers who contribute stories can often create situations that demand clarification or revision. Retcons also often appear in manga, soap operas, serial dramas, movie sequels, cartoons, professional wrestling angles, video games, radio series, and other forms of serial fiction.

The first published use of the phrase "retroactive continuity" is found in theologian E. Frank Tupper's 1973 book The Theology of Wolfhart Pannenberg: "Pannenberg's conception of retroactive continuity ultimately means that history flows fundamentally from the future into the past, that the future is not basically a product of the past."

The first known printed use of "retroactive continuity" referring to the altering of history within a fictional work is in All-Star Squadron #18 (February 1983) from DC Comics. The series was set on DC's Earth-Two, an alternate universe in which Golden Age comic characters age in real time. All-Star Squadron was set during World War II on Earth-Two; as it was in the past of an alternate universe, all its events had repercussions on the contemporary continuity of the DC multiverse. Each issue changed the history of the fictional world in which it was set. In the letters column, a reader remarked that the comic "must make you [the creators] feel at times as if you're painting yourself into a corner", and, "Your matching of Golden Age comics history with new plotlines has been an artistic (and I hope financial!) success." Writer Roy Thomas responded, "we like to think that an enthusiastic ALL-STAR booster at one of Adam Malin's Creation Conventions in San Diego came up with the best name for it a few months back: 'Retroactive Continuity'. Has kind of a ring to it, don't you think?" The term then took firm root in the consciousness of fans of American superhero comics.

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