Cultural Marxism is a far-right antisemitic conspiracy theory that misrepresents Western Marxism (especially the Frankfurt School) as being responsible for modern progressive movements, identity politics, and political correctness. The conspiracy theory posits that there is an ongoing and intentional academic and intellectual effort to subvert Western society via a planned culture war that undermines the supposed Christian values of traditionalist conservatism and seeks to replace them with culturally progressive values.
A revival of the Nazi propaganda term "Cultural Bolshevism", the contemporary version of the conspiracy theory originated in the United States during the 1990s. Originally found only on the far-right political fringe, the term began to enter mainstream discourse in the 2010s and is now found globally. The conspiracy theory of a Marxist culture war is promoted by right-wing politicians, fundamentalist religious leaders, political commentators in mainstream print and television media, and white supremacist terrorists, and has been described as "a foundational element of the alt-right worldview". Scholarly analysis of the conspiracy theory has concluded that it has no basis in fact.