The Allied invasion of Normandy was among the largest military operations ever staged, marking the beginning of the campaign to liberate North-West Europe from German occupation. But how much do you know about D-Day?
Below are some key facts on the planning and execution of the Allied invasion.
The D-Day rehearsal that cost 700+ lives.
In late April 1944, Allied forces conducted a disastrous dress rehearsal of the Normandy invasion on an evacuated Devon beach at Slapton Sands. Known as “Exercise Tiger,” 700+ U.S. troops lost their lives after a fleet of German E-boats were alerted by heavy radio traffic in Lyme Bay and intercepted the three-mile-long convoy of vessels and torpedoed American tank landing ships. The tragedy was kept a top secret. The survivors were strictly ordered not to talk about it.
The D-Day invasion took years of planning.
Allied leaders Franklin Roosevelt and Winston Churchill knew from the start of the war that a massive invasion of mainland Europe would be critical to relieve pressure from the Soviet army fighting the Germans in the East. Initially, a plan called “Operation Sledgehammer” called for an Allied invasion of ports in northwest France as early as 1943, but Roosevelt and Churchill decided to invade Northern Africa first and attack Europe’s “soft underbelly” through Italy. The success of this strategy in WW2 meant that Italy was disabled and Germany weakened by the time the Allies invaded France in 1944.
British, American and Canadian officers submitted plans for the cross-channel invasion in July 1943. Although limited planning for an invasion of Europe began soon after the evacuation of Dunkirk in 1940, detailed preparations for Operation 'Overlord' did not begin until after the Tehran Conference in late 1943.
The planners were particular about the timing of the invasion. They wanted a full moon, with a spring tide. They wanted to land at dawn on a flood tide when it was about half way in. That meant there were only a few days that were appropriate. June 4th was selected but the weather was so bad that the invasion had to be delayed for one day. On the 5th, though conditions were still terrible, there was some slight hope of improvement. Appalled by the chaos which would ensure if there was more delay, Eisenhower decided that the risk must be taken: D-Day would be June 6th.
What does D-Day stand for?
Unlike V-E Day (“Victory in Europe”), the “D” in D-Day isn’t short for “dreadnought” or “decision.” The earliest known reference goes back to 1917, but early in the Second World War, it was called ‘Dog-Day’ after the phonetic alphabet of the day. It was used during Operation WATCHTOWER, the US invasion of Guadalcanal in the South Pacific, for example. Later, it became simply known as ‘D-Day’ and was used for all major amphibious operations including north-west Africa, Sicily and southern Italy. Thus, the day before June 6th, 1944, was known as D-1 and the days after were D+1, D+2, D+ and so on. One reason was to keep the actual date out of the hands of spies; another was to serve as a placeholder until an actual date was chosen. They also used H-Hour for the specific time of the launch.
Allied forces carried out a massive deception campaign in advance of D-Day.
‘Brutus’, a Polish triple agent who had led a resistance network in France and, when caught, volunteered to spy for the Germans in London, only to turn himself over to British intelligence, provided his German handlers with details of multiple units of troops amassing in the south of England, close to the coastline of Pas de Calais. ‘Tricycle’, a German-hating Yugoslavian playboy-turned-double-agent, sent very similar reports. Meanwhile ‘Treasure’, a Russian-born Frenchwoman based in the West Country, reported seeing very few troops gathered opposite Normandy. ‘Garbo’ had the most delicate job of all. The resourceful Spaniard, who had previously flummoxed the Germans by sending reports from ‘London’ when he was actually in Lisbon, and now controlled a fictional network of spies in the British capital, first fed information suggesting an attack on Pas de Calais, then repeatedly tried to warn of the attack on Normandy once it was too late to do anything about it, to win the Germans’ trust. Finally, on 9 June 1944, when the 1st Panzer Division and another armoured division were on their way to tackle troops at Normandy, he reported once more that a large force was collecting opposite Pas de Calais. Hitler diverted the reinforcements back to Calais, and the British lived to fight another day.
Even a “phantom army,” commanded by American General George Patton, was used to throw Germany off the scent.
WWII D-Day Paradummys.
Paradummies were used as a decoy during the WWII D-Day landings in order to deceive the Germans into believing that a large force had landed, drawing their troops away from the real landing zones. You may remember them featuring in the well-known D-Day movie 'The Longest Day'.
Nicknamed Ruperts, the fake parachutists were made from hessian cloth bags and filled with sand and straw, arranged to resemble a human figure. And even though they were just under 3ft tall — much smaller than real soldiers, to people looking up at them from the ground and against a dark sky — they were actually pretty deceiving. The deception was known as ‘Operation Titanic’ in which 500 fake cloth dolls each attached to a parachute were dropped in four different locations all over Normandy while the real Allied airmen landed in their targeted drop zones.
Germany had a massive coastal defensive system.
Anticipating an Allied invasion somewhere along the French coast, Adolf Hitler charged Field Marshal Erwin Rommel with fortifying German defences in France. The Atlantic Wall was the name given to a massive coastal defensive structure that stretched all the way from Norway, along the Belgium and French coastline to the Spanish border. The Atlantic Wall covered a distance of 1,670 miles and it formed the main part of Hitler’s ‘Fortress Europe’. Artillery emplacements were supported with machine gun posts and other artillery emplacements were built inland to give the Wall some form of protection when the expected Allied landings took place. Beaches along the northern coastline of France were strewn with anti-tank and anti-vehicle obstacles known as ‘Rommel’s Teeth’. Many of these had mines attached to them so that at high tide both the ‘teeth’ and the mines would not have been seen by an invading force.
It’s estimated that six million mines were laid on beaches in Northern France.
D-Day Message from General Dwight D. Eisenhower
The following Order of the Day was issued on 6th June, 1944. D-Day, by General Eisenhower, Supreme Commander Allied Expeditionary Force, to each individual of the Allied Expeditionary Force.
“Soldiers, Sailors and Airmen of the Allied Expeditionary Force! You are about to embark upon a great crusade, toward which we have striven these many months. The eyes of the world are upon you. The hopes and prayers of liberty loving people everywhere march with you. In company with our brave Allies and brothers in arms on other fronts, you will bring about the destruction of the German war machine, the elimination of Nazi tyranny over the oppressed peoples of Europe, and security for ourselves in a free world. Your task will not be an easy one. Your enemy is well trained, well equipped and battle hardened, he will fight savagely. But this is the year 1944! Much has happened since the Nazi triumphs of 1940-41. The United Nations have inflicted upon the Germans great defeats, in open battle, man to man. Our air offensive has seriously reduced their strength in the air and their capacity to wage war on the ground. Our home fronts have given us an overwhelming superiority in weapons and munitions of war, and placed at our disposal great reserves of trained fighting men. The tide has turned! The free men of the world are marching together to victory! I have full confidence in your courage, devotion to duty and skill in battle. We will accept nothing less than full victory! Good Luck! And let us all beseech the blessings of Almighty God upon this great and noble undertaking.”- Gen. Dwight D. Eisenhower
Paratroopers launched the operation before dawn.
The D-Day invasion began in the pre-dawn hours of June 6th, over 18,000 men of the US 82nd and 101st Airborne Divisions and the British 6th Airborne Division were dropped into Normandy. Allied paratroopers and glider-borne infantry were well trained and highly skilled, but for many this was their first experience of combat. Their objectives were to cut off exits and destroy bridges to slow German reinforcements and to secure the flanks of the assault areas.
D-Day was carried out along five sections of beachfront.
Operation Overlord was divided among sections of beachfront along the Normandy coast codenamed, from West to East: “Utah”, (undertaken by United States Army troops), “Omaha,” (undertaken by United States Army troops) “Gold,” (undertaken by British Army troops) “Juno” (undertaken by Canadian Army troops) and “Sword.” (undertaken by British Army troops).
On ‘Bloody Omaha’ where around 4000 men were killed or wounded, one American unit landing in the first wave, lost 90% of its men. On Gold Beach, by contrast, casualty rates were around 80% lower.
The night before the landings nervous Prime Minister Winston Churchill said to his wife: “Do you realise that by the time you wake up in the morning 20,000 men may have been killed?”
More than 156,000 Allied ground troops stormed the beaches.
US troops went ashore on the landing beaches at 6.31am in wave after wave of landing ships, followed an hour later by the British and Canadians on their beaches. There were 61,715 British troops, 21,400 Canadian soldiers and 73,000 Americans.
In the following weeks after D-Day, the Allies fought their way across the Normandy countryside in the face of determined German resistance and by the end of June, the Allies had seized the vital port of Cherbourg, landed approximately 850,000 men and 150,000 vehicles in Normandy, and were poised to continue their march across France.
The toughest fighting was on Omaha Beach.
At Omaha Beach, bombing runs had failed to take out heavily fortified German artillery positions. The first waves of American troops were cut down in droves by heavy German machine gun fire as they scrambled across the mine-riddled beach. But U.S. forces persisted through the day, pushing forward to a fortified seawall and then up steep bluffs to take out the German artillery posts by nightfall. All told, around 2,400 American troops were killed, wounded or unaccounted for after the fighting at Omaha Beach.
Despite Eisenhower's concerns about the Omaha beach situation, by mid-afternoon it was clear that even on Omaha the battle was running in the Allies' favour. Churchill addressed the House of Commons at 6pm to announce an “astounding success”.
D-Day was an international effort.
By 1944, over 2 million troops from over 12 countries were in Britain in preparation for the Normandy invasion. On D-Day, Allied forces consisted primarily of American, British and Canadian troops but also included Australian, Belgian, Czech, Dutch, French, Greek, New Zealand, Norwegian, Rhodesian and Polish naval, air or ground support.
Floating Harbours to facilitate the rapid offloading of cargo onto beaches during the Allied invasion.
Five days after the D-Day invasion, troops immediately began installing two massive temporary harbours that had taken six months to construct back in England. Mulberry was the codename for all the various different structures that would create the artificial harbours.
The harbour at Gold Beach was used for 10 months after D-Day and over 2.5 million men, 500,000 vehicles, and 4 million tons of supplies were landed before it was fully decommissioned.
The D-Day Casualties.
The First U.S. Army, accounting for the first 24hrs in Normandy, tabulated 1,465 killed, 1,928 missing, and 6,603 wounded. The after-action report of U.S. VII Corps (ending 1 July) showed 22,119 casualties including 2,811 killed, 5,665 missing, 79 prisoners, and 13,564 wounded, including paratroopers.
Canadian forces at Juno Beach sustained 946 casualties, of whom 335 were listed as killed.
British figures estimate 2,500 to 3,000 killed, wounded, and missing, including 650 from the Sixth Airborne Division.
German sources estimate 9,000 thousand D-Day casualties on 6 June
The total number of casualties that occurred during Operation Overlord, from June 6th (the date of D-Day) to August 30th (when German forces retreated across the Seine) was over 425,000 Allied and German troops. This figure includes over 209,000 Allied casualties.
The Normandy invasion made a vital psychological blow to the enemy and prevented Hitler from sending troops from France to build up his Eastern Front. By May 8, 1945, Hitler had committed suicide and the Allies formally accepted the unconditional surrender of Nazi Germany.
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