In reaction to the bombing of Pearl Harbor on December 7, 1941, President Franklin Roosevelt signed Executive Order 9066 in early 1942, which allowed the U.S. military to declare the West Coast part of the Pacific Theater. It identified all people of Japanese descent, including Japanese Americans, as potential enemies of the state.
It required that all people of Japanese descent, up to 70% of whom were American citizens, be interred in isolated camps across the United States. People were given only 48 hours to pack essentials and secure their land, businesses, homes, and vehicles. If they were unable to find anyone to care for their property or belongings, it was confiscated and sold. Many families lost everything.
The internment camps were located in isolated sections of the country, many in brutal climates, and the cramped, uninsulated, army-style barracks housed four or five families per building. Most lived in these conditions until the end of the war in 1945.
Locally, there were two internment camps in Arizona, one on the Gila River Indian Reservation (over their adamant objections on civil rights grounds) and one in Poston, Arizona.
In 1976, President Ford officially repealed Executive Order 9066, but it wasn't until 1988 that Congress passed, and President Reagan signed, Public Law 100-383, which acknowledged the injustice of internment, apologized for it, and provided a $20,000 cash payment to each person who was interned.
To learn more, visit https://www.archives.gov.