In World War II, Dieppe was the site of a Allied attack on Nazi German occupied France on August 19, 1942. It was code named Operation Jubilee for over 6,000 men, mainly Canadian soldiers to attack the beach, march inland, disrupt German defences and retreat back to the beach and wait for evacuation.
The raid was a military disaster, as the 2nd Canadian Infantry division failed to make it off the beach, and more than 900 men were killed and another 2340 were taken prisoner or captured in the face of 1500 well protected German defenders. The Allied air forces failed to lure the Luftwaffe into open battle, and would loose 119 planes, and the Royal Navy suffered 555 casualties supporting the landings.
The defeat at Dieppe yielded important lessons for Operation Torch (the invasion of Africa) and Operation Overlord (the D-Day Invasion).