As has been widely reported, the alleged shooter in the Christchurch massacre in New Zealand subscribed to a racist conspiracy theory that national and world governments are trying to eliminate white people by encouraging immigration of non-white people, intermarriage between white people and non-white people, abortion, and, in the more paranoid versions of the theory, violence against white people. This theory fuels racism, anti-Semitism, xenophobia, and Islamophobia and can inspire violence like that seen in Christchurch: the shooter killed fifty Muslim worshippers and injured fifty more. He titled his manifesto “The Great Replacement” after a version of this theory articulated in France; in the U.S. this theory has often been known as “white genocide” or “white extinction.” The Christchurch shooting brought this theory widespread attention but it has a long history among hate groups and, more recently, in more mainstream circles. And as with other hateful ideologies, Greco-Roman antiquity is frequently invoked in support of it, by giving legitimacy to the idea that white people are somehow endangered.