A political myth is a narrative, usually in the form of a dramatic story, which relates to a political topic. A political myth might claim to explain how a particular state came to be or describe the relationship between two groups as part of a larger, legendary narrative. Political myths, whether they have any basis in historical fact or not, satisfy a group's need to have current a current political situation legitimized by inclusion in a larger story.
The term "political myth" was coined in 1975 in Henry Tudor's book of the same name. Tudor described this type of myth as a myth in which the hero or protagonist was not a single person but a group. The group might be a nation, an ethnic group or a social class. Political myths relate to history but are not necessarily historical; group members accept the myth as valid in philosophical terms rather than as historically accurate.
One common type of political myth is the national origin story or ethnogenesis. Many nations have semi-legendary accounts, often based to some extent on historical fact, of how they came into existence. For example, early medieval historians recounted the arrival of the English in England under two mythical leaders, Hengist and Horsa, while medieval historian Snorri Sturluson created a mythic origin for the Scandinavian peoples that linked them to Classical mythology. A more modern example of this type of myth would be the story of Puritans sailing to the New World to escape religious persecution and founding what would become America.
Not every political myth is an origin story. Other political myths provide a grand narrative to frame political and cultural movements. For instance, the westward expansion of the United States in the 19th century was accompanied by the creation of a political myth known as Manifest Destiny. This narrative explained American territorial acquisition as part of an inevitable growth. Proponents perceived reaching the Pacific ocean as the United States's "destiny." The US itself became the protagonist of this myth, with resistance to American expansion perceived as being a threat to the national destiny.
The role of political myth is to unite the community and instill a sense of belonging. This can have both positive and negative consequences. Political myths often serve as rallying points in times of national crisis, but they can also be used as tools of oppression. For instance, the "dolchstosslegende," or "stab-in-the-back legend," was a narrative which claimed that Germany had lost the First World War due to betrayal by internal enemies. It was a major element of Nazi propaganda and encouraged support for the regime.