The recent mass shooting in Buffalo has focused attention on ideas termed the “great replacement theory”—that there’s a conspiracy to disempower white Americans. To historians, today is far from the first time that concerns about immigration and cultural change have taken on forms of replacement theory. 

Especially since the 2016 election of Donald Trump, which itself followed decades of failure to reform the country’s immigration system, such concerns have again started to rise, says Michael Barkun, professor emeritus of political science. “It’s not simply white supremacists who are pushing this,” he says. “It’s one of the cycles of nativism that appear periodically in America whenever you have an upswing in immigration.”

Read more in the Christian Science Monitor article, "‘Replacement theory’: The view from an immigration-wary Georgia district."