Entitled: 'Reading evacuation orders on bulletin board at Mary Knoll mission, Los Angeles, California.' The internment of Japanese-Americans during WWII was the forced relocation and incarceration in camps of 110,000-120,000 people of Japanese ancestry (62% of the internees were US citizens) ordered by President Roosevelt shortly after Japan's attack on Pearl Harbor. Japanese-Americans were incarcerated based on local population concentrations and regional politics. Stock Photo