In 1953, a group of prisoners of war who had fought against the communist invasion of South Korea were released. They chose - apparently freely - to move to Mao's China. Among those refusing repatriation were twenty-one American GIs. Their decision sparked alarm in the West: why didn't they want to come home? What was going on?

Soon, people were saying that the POWs' had been 'brainwashed'. Was this something new or a phenomenon that has been around for centuries? Today, brainwashing is almost taken for granted - built into our psychological and political language, rooted in the way we think about minds and societies. Historian of science Daniel Pick joins the podcast to reveal how we got to this point, and why.

Find out more about the Hidden Persuaders research group at Birkbeck here.

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