High Quality Content by WIKIPEDIA articles! Yasui v. United States, 320 U.S. 115 (1943) was a United States Supreme Court case regarding the constitutionality of curfews used during World War II when they were applied to citizens of the United States. The case arose out of the implementation of Executive Order 9066 by the U.S. military to create zones of exclusion along the West Coast of the United States where Japanese-Americans were subjected to curfews and eventual removal to relocation centers. This Presidential order followed the Japanese Attack on Pearl Harbor in 1941 that brought America into World War II and inflamed the existing anti-Japanese sentiment in the country.