During World War II, Operation Ironside was a deception carried out by the Allies in 1944 in support of the invasion of Normandy. Ironside falsely threatened an Allied invasion of France along the Bay of Biscay, near Bordeaux during the summer of 1944.
Ironside was part of the deception of Operation Fortitude.
Roger Hesketh, Fortitude: The D-Day Deception Campaign (Overlook, 2000, New York) details the plans for Ironside and Ironside II