How does wartime violence affect public attitudes toward the government in the long run? In this paper, we examine whether violence against civilians during the Korean War continues to influence people’s attitudes toward the South Korean government more than half a century later. We find that wartime violence has clear long-term attitudinal effects. Using a difference-in-differences analysis that compares the cohorts born before and after the war, the findings indicate that people who experienced violence in their childhood (0–5 years) are less supportive of the South Korean government, especially the administration and the military, compared with those born in the same areas during the 5 years after the war. We argue that the gap between pre- and post-war cohorts is generated by the long-lasting trauma of wartime violence and the social stigma imposed on violence victims after the war.