Alternative history or alternate history can be:

• A genre of science fiction: see Alternative history (fiction).
• The academic extrapolation of alternate outcomes of historical events: see virtual history.
• A construction of past events which is refuted in verifiable or otherwise generally accepted sources: see historical revisionism. Support for the history is generally undocumented or poorly documented. Belief in such histories are often based in belief of a conspiracy theory to explain its lack of documentation.
• A History told from an alternative viewpoint, such as a indigenous people rather than a explorer of them. For example: "Herstory" or history from a female perspective.