In December 2024, South Korean president Yoon Seok-yeol stunned the world by declaring martial law. More puzzling was that Yoon's insurrection unexpectedly gained substantial support from the ruling right-wing party and many citizens. Why do ordinary citizens support authoritarian leaders and martial law in a democratic country? What draws them to extreme actions and ideas? With the rise of illiberal, far-right politics across the globe, Reactionary Politics in South Korea provides an in-depth account of the ideas and practices of far-right groups and organizations threatening democratic systems. Drawing on eighteen months of field research and rich qualitative data, Myungji Yang helps explain the roots of current democratic regression. Yang provides vivid details of on-the-ground internal dynamics of far-right actors and their communities and worldviews, uncovering the organizational and popular foundations of far-right politics and movements.