How the Allies fooled their enemies during WWII
Syndrome K

The Italian campaign led to the downfall of Benito Mussolini. Hitler, fearing Rome would be taken by the Allies, ordered its occupation by the Wehrmacht. Previously spared ill-treatment, Rome's Jewish population was now in a perilous position. Many sought refuge in Fatebenefratelli Hospital, on Tiber Island.

The ruse allowed hundreds of Italian Jews to escape the clutches of the Gestapo. In June 1944, Allied forces—specifically the US Fifth Army—liberated Rome.
Tricking Rommel at El Alamein

Operation Cascade and Operation Bertram were both designed by the Allies to deceive Rommel (pictured). Cascade was conceived to create a false order of battle in order to keep the Axis guessing as to the strength of the Allies in the region. This was achieved using bogus troop formations, radio traffic, and double agents.