The present study investigated transgenerational impacts of the World War II United States (U.S.) incarceration of Japanese Americans among the grandchildren of those who were imprisoned. Fourth-generation (Yonsei) Japanese Americans responded to open-ended online survey questions asking them to describe how the past incarceration and their grandparents' wartime trauma impacted their life. Qualitative analyses of participants' responses identified the range and relative frequency of multiple incarceration impacts, as well as four key themes: (a) Identity, Assimilation, and Culture Loss, (b) Intergenerational and Family Dynamics, (c) Agency, Advocacy, and Social Justice, and (d) Societal Views and Wariness About the U.S. Government. Findings indicate the presence of ongoing historical trauma impacts for the grandchildren of Japanese American incarceration survivors, two generations after World War II.