Executive Order 9066 was a United States presidential executive order signed and issued during World War II by United States president Franklin D. Roosevelt on February 19, 1942. "This order authorized the forced removal of all persons deemed a threat to national security from the West Coast to "relocation centers" further inland—resulting in the incarceration of Japanese Americans." Two-thirds of the 125,000 people displaced were U.S. citizens.

In the United States, an executive order is a directive by the president of the United States that manages operations of the federal government. The legal or constitutional basis for executive orders has multiple sources. Article Two of the United States Constitution gives presidents broad executive and enforcement authority to use their discretion to determine how to enforce the law or to otherwise manage the resources and staff of the executive branch. The ability to make such orders is also based on expressed or implied Acts of Congress that delegate to the president some degree of discretionary power. The vast majority of executive orders are proposed by federal agencies before being issued by the president.