Internment facility for Japanese Americans during World War II .
Fear that Japan would invade the western U.S. with the aid of spies living in the U.S. led the government to force Japanese Americans in western states to relocate to one of ten camps, of which Manzanar, in California, was the first to be established and the best known. During its operation, over 11,000 people were confined there. The California centre was named an national historic site in 1992.