In historiography, the term historical revisionism identifies the re-interpretation of the historical record. It usually means challenging the orthodox views held by professional scholars about a historical event, or introducing new evidence, or of restating the motivations and decisions of the participant people. The revision of the historical record reflects the new discoveries of fact, evidence, and interpretation, which produce a revised history. In dramatic cases, revisionism involves a reversal of older moral judgments about heroes and villains.
At a basic level, historical revisionism is a common and not especially controversial process of developing and refining the writing of history. Much more controversial is the reversal of moral findings, which the heroes, good guys, or positive forces are depicted as villains, bad guys, or negative forces. This revisionism is quickly challenged by the supporters of the old view, often in heated terms. It becomes historical negationism, a form of historical revisionism that presents a re-interpretation of the moral meaning of the historical record. A famous example is the revisionism on the causes of World War I, in which the revisionists of the 1920s denied that Germany was the guilty party. The term "revisionism" is used pejoratively by people who charge that revisionists are deliberately distorting the true historical record.
Historical revisionism is the means by which the historical record — the history of a society, as understood in their collective memory — continually integrates new facts and interpretations of the events commonly understood as history; about which the historian James M. McPherson, said:
The fourteen-thousand members of this Association, however, know that revision is the lifeblood of historical scholarship. History is a continuing dialogue, between the present and the past. Interpretations of the past are subject to change in response to new evidence, new questions asked of the evidence, new perspectives gained by the passage of time. There is no single, eternal, and immutable “truth” about past events and their meaning.