Political forgery

Black propaganda is false information and material that purports to be from a source on one side of a conflict, but is actually from the opposing side. It is typically used to vilify, embarrass, or misrepresent the enemy. Black propaganda contrasts with grey propaganda, the source of which is not identified, and white propaganda, in which the real source is declared and usually more accurate information is given, albeit slanted, distorted and omissive. Black propaganda is covert in nature in that its aims, identity, significance, and sources are hidden.

The major characteristic of black propaganda is that the people are not aware that someone is influencing them, and do not feel that they are being pushed in a certain direction. Black propaganda purports to emanate from a source other than the true source. This type of propaganda is associated with covert psychological operations. Sometimes the source is concealed or credited to a false authority and spreads lies, fabrications, and deceptions. Black propaganda is the "big lie", including all types of creative deceit. Black propaganda relies on the willingness of the receiver to accept the credibility of the source. If the creators or senders of the black propaganda message do not adequately understand their intended audience, the message may be misunderstood, seem suspicious, or fail altogether.

Governments conduct black propaganda for reasons that include: A) by disguising their direct involvement a government may be more likely to succeed in convincing an otherwise unbelieving target audience, and B) there are diplomatic reasons behind the use of black propaganda. Black propaganda is necessary to obfuscate a government's involvement in activities that may be detrimental to its foreign policies.

Benjamin Franklin created and circulated a fake supplement to a Boston newspaper that included letters on Indian atrocities and the treatment of American prisoners.

In the United Kingdom, the Political Warfare Executive operated a number of black propaganda radio stations. Gustav Siegfried Eins (GS1) was one of the first such stations—purporting to be a clandestine German station. The speaker, "Der Chef", purported to be a Nazi extremist, accusing Hitler and his henchmen of going soft. The station focused on alleged corruption and sexual improprieties of Nazi Party members.

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