During World War II , the United States forcibly relocated and incarcerated at least 125,284 people of Japanese descent in 75 identified incarceration sites. Most lived on the Pacific Coast, in concentration camps in the western interior of the country. Approximately two-thirds of the inmates were United States citizens.
These actions were initiated by president Franklin D. Roosevelt via an executive order shortly after Imperial Japan's Attack on Pearl Harbor.
Japanese Americans were placed in concentration camps based on local population concentrations and regional politics. More than 112,000 Japanese Americans who were living on the West Coast were incarcerated in camps which were located in its interior. California defined anyone with 1⁄16th or more Japanese lineage as a person who should be incarcerated.
Here is a short video explaining the Japanese incarceration camps:
YOUTUBE hI4NoVWq87M Ugly History: Japanese American incarceration camps
Yasui Story: Learn more about one family's fight for justice against Japanese internment