The crushing defeats the Allies suffered since 1939 were beginning to take their toll on Allied morale. Even though the Battle of Britain had staved off German victory, little success had happened since then.
Most of occupied Europe had been under Nazi domination for at least two years. While there was no immediate threat of the Allies losing the war, the Allied command, especially the British, wanted to win a battle in order to raise morale at home and abroad.
During the Battle of Britain the United Kingdom mobilized armies and brought them to England to drive off the expected invasion. While most units were too late to be a factor in dissuading the Germans for attacking, the armies did remain in case they were needed. One such unit was the Canadian 2nd Division. Landing in England in 1940, they were training for two years without seeing combat. The men were restless, sick of endless training and bad food.
Meanwhile, a young officer took command of new force called Combined Operations. A hero in the Battle of Crete, Lord Louis Mountbatten, was tasked with developing missions that would test the new doctrine of amphibious landings. Directing massive air, sea, and land forces, Mountbatten”s staff had no idea of what to do with them. Should they land in France and hold a port to see if the real invasion should land there? Should they conduct reconnaissance-in-force missions to test German defenses? The lack of a clear mission hampered planning as Combined Operations was unsure of its own mission. Mountbatten, flamboyant, famous before the war as a grandson of Queen Victoria, did not intend to fail at his mission, whatever it was.
These three events collided in the surf of the little French port of Dieppe. With limited port facilities, Dieppe was close the English coast in the Pas-de-Calais. An important consideration was the distance of Dieppe from English airfields. Fighters could cover the operation without running out of fuel prematurely.
Finally Combined Operations outlined the plan: A small force, mostly Canadian 2nd Division soldiers but with Royal Marines and 68 US Army Rangers making the US European ground combat debut, would seize Dieppe and hold it for forty-eight hours. The RAF would engage and destroy the German opposition in the air to reduce the German Luftwaffe.
Almost from the start Combined Operations doomed the plan and the men that would carry it out. Reconnaissance was incomplete, and did not reveal the extent of the German defenses, which included an underwater minefield, many coastal guns, and airfields and reinforcements that could bolster the town”s garrison. The regular passage of E-boats, German patrol boats armed with guns and torpedoes, was not noted.
When the invasion fleet left England, it ran straight into an E-boat patrol. The Germans set up a deadly crossfire that hit many ships. Casualties began even before the first soldier landed on the shores of Dieppe.
That morning, by chance, the Germans held an anti-invasion exercise. The Canadians walked into a fully awakened and armed garrison, and the slaughter began. By 9 AM it was obvious that the battle was lost and destroyers moved in to get as many men off the beach as they could. Like Dunkerque two years earlier, an Allied army was driven off the French Coast.
Casualties were high. Out of 5,000 Canadians, 3,367 were casualties, including over 1,900 prisoners-of-war. Nine hundred were dead. Worse, the massive Allied airpower was severely mauled by the Luftwaffe. Most of the Allied heavy equipment was left on the beach.
Later apologists for Mountbatten would characterize Dieppe as an expensive but important lesson for the Normandy landings. By the time the North African landings took place on November 8, 1942, new landing craft specialized for all sorts of tasks were arriving. The Dieppe raid convinced the Allied Overlord planners that landing on open beaches were preferable to trying to hold a port in the first few hours.
Dieppe did convince the Germans that the Allies would attack a port in the main invasion, and that may have helped the Normandy landings two years later. In that landing, the Canadian 2nd Division would exact revenge on the same German units that drove them off the beaches of Dieppe.