In the aftermath of Imperial Japan's attack on Pearl Harbor, President Franklin D. Roosevelt had issued Executive Order 9066 on February 19, 1942, authorizing the War Department to create military areas from which any or all Americans might be excluded. Subsequently, the Western Defense Command, a United States Army military command charged with coordinating the defense of the West Coast of the United States, ordered "all persons of Japanese ancestry, including aliens and non-aliens" to relocate to internment camps. However, a 23-year-old Japanese-American man, Fred Korematsu, refused to leave the exclusion zone and instead challenged the order on the grounds that it violated the fourteenth Amendment.