Fred Toyosaburo Korematsu was an American civil rights activist who resisted the internment of Japanese Americans during World War II. Shortly after the Imperial Japanese Navy launched its attack on Pearl Harbor, President Franklin D. Roosevelt issued Executive Order 9066, which authorized the removal of individuals of Japanese ancestry living on the West Coast from their homes and their mandatory imprisonment in incarceration camps, but Korematsu instead challenged the orders and became a fugitive.

During World War II, the United States forcibly relocated and incarcerated about 120,000 people of Japanese descent in ten concentration camps operated by the War Relocation Authority (WRA), mostly in the western interior of the country. Approximately two-thirds of the detainees were United States citizens. These actions were initiated by Executive Order 9066, issued by President Franklin D. Roosevelt on February 19, 1942, following Imperial Japan's attack on Pearl Harbor in December 1941. Before the war, about 127,000 Japanese Americans lived in the continental United States, of which about 112,000 lived on the West Coast. About 80,000 were Nisei and Sansei. The rest were Issei immigrants born in Japan, who were ineligible for citizenship. In Hawaii, where more than 150,000 Japanese Americans comprised more than one-third of the territory's population, only 1,200 to 1,800 were incarcerated.