Events and Ideas #7 Battle of the Atlantic U.S. History Unit 5

Essential Questions: What were the key elements of the Battle of the Atlantic? What things gave the Allies the advantage to win control over the Atlantic Ocean?

U-boat shells a merchant ship Battle of the Atlantic The Battle of the Atlantic was the longest continuous military campaign in World War II: 1939 -1945 After declaring war on the U.S., German submarines entered American coastal waters. U-boat shells a merchant ship

United States East Coast American merchant ships were targeted by German U-boats They attacked at night when the glow from the cities silhouetted the vessels. People on the East Coast dimmed their evening lights, put up “blackout curtains” and drove with their headlights off. What have we changed since 9/11? Airport security Passports to go in and out of Mexico/Canada Homeland Security Act 2002 – Large security force, wiretapping, internet watch

German U-boats at anchor By Aug. 1942, German submarines had sunk 360 American ships. So many oil tankards had been sunk, that gasoline and oil had to be rationed Cargo ships began to travel in convoys escorted by Navy ships to ensure safety German U-boats at anchor The British adopted a convoy system, initially voluntary and later compulsory for almost all merchant ships, the moment that World War II was declared. Each convoy consisted of between 30 and 70 mostly unarmed merchant ships. American and Canadian supplies were vital for Britain to continue its war effort.

Convoy System Great Britain required more than a million tons of imported material per week in order to survive and hold off Germany’s attacks. Blimps and airplanes flew overhead keeping watch. At the core of the battle was the blockade of Germany, and Germany's blockade of Great Britain At its core was the Allied naval blockade of Germany, announced the day after the declaration of war, and Germany's subsequent counter-blockade U.S. Navy blimp flies over a convoy of ships to protect it from German U-boats

A fleet of U.S. Liberty ships Mass Production Even though the Germans wreaked havoc on Allied ships in the Atlantic, by 1942 U.S. shipyards are producing ships faster than the Germans are sinking them New technology helps turn the tide in favor of the allies Sonar, Radar, Depth Charges Liberty ships were cargo ships built in the United States during World War II. They were cheap and quick to build, and came to symbolize U.S. wartime industrial output. Based on vessels ordered by Britain to replace ships torpedoed by German U-boats, they were purchased for the U.S. fleet and for lend-lease deliveries of war materiel to Britain and to the Soviet Union. Eighteen American shipyards built 2,710 Liberty ships between 1941 and 1945, easily the largest number of ships produced to a single design. A fleet of U.S. Liberty ships

D-Day Plan

Symbol of the fictitious 1st Army unit D-Day Deception Efforts to fool the Germans into thinking the invasion would occur elsewhere Method used: Controlled leaks of misinformation Physical deception Fake infrastructure and equipment Dummy landing craft Dummy aircraft/airfields Decoy lighting Fake messages/transmissions Messages sent to and from fake units Dummy aircraft For deceptions the Allies had developed a number of methodologies, referred to as "special means". They included combinations of physical deception, fake wireless activity, leaks through diplomatic channels, and double agents. Fortitude used all of these techniques to various extents. For example, Fortitude North relied heavily on wireless transmission (the Allies thought that Scotland was too far for German reconnaissance to reach) whilst Fortitude South utilized the Allies network of double agents. Physical deception: to mislead the enemy with nonexistent units through fake infrastructure and equipment, such as dummy landing craft, dummy airfields, and decoy lighting. Controlled leaks of information through diplomatic channels, which might be passed on via neutral countries to the Germans. Wireless traffic: To mislead the enemy, wireless traffic was created to simulate actual units Use of German agents controlled by the Allies through the Double Cross System to send false information to the German intelligence services Public presence of notable staff associated with phantom groups, such as FUSAG (First U.S. Army Group), most notably the well-known US general George S. Patton. Symbol of the fictitious 1st Army unit

The Normandy Invasion June 6, 1944 “D-Day” aka “Operation Overlord” The attack was planned months in advance; the Nazi’s knew the Allies planned to attack…but didn’t know where Five “Landing Beaches” were chosen: Utah, Omaha, Gold, Sword, and Juno D-Day map of the coast of France

Troops & equipment landing at a captured beachhead The Normandy Invasion Largest single allied invasion in the war 1.5 million troops & 5 million tons of equipment sent to Britain in preparation Dawn of June 6: 7,000 ships, 100,000 soldiers, 23,000 paratroopers land on the Normandy beaches Troops & equipment landing at a captured beachhead

Battle of the Atlantic Fill out the graphic organizer “Battle of the Atlantic” while viewing the next seven slides

Sept. 16th – 1st Convoy route 1939 totals: 165 merchant ships sunk Sept 3, 1939 - WWII begins Set. 14th – 1st U-boat suck Sept. 16th – 1st Convoy route 1939 totals – 165 merchant ships sunk 9 U-boats sunk Sept 3, 1939 - WWII begins Set. 14th – 1st U-boat suck Sept. 16th – 1st Convoy route 1939 totals: 165 merchant ships sunk 9 U-boats sunk

June – Dunkirk evacuated June - France surrenders to Germany Oct. 19-20 – 35 merchant ships sunk – largest 48 hour merchant ship loss of the war June – Dunkirk evacuated June - France surrenders to Germany July – Battle of the Atlantic officially begins 1940 totals: 567 merchant ships sunk 24 U-boats sunk

Jan–April: German aircraft sink 113 ships in Atlantic March – 1st radar detect U-boats June – German Naval code broken Hitler declares war on U.S.A. 1941 totals: 503 merchant ships sunk 35 U-boats sunk

Feb – Germany changes enigma machine, British can’t read code Germany changes code U-boats begin surface nigh attacks British break U-boat code Feb – Germany changes enigma machine, British can’t read code May - U-boats begin night time surface attacks June - British cryptographers crack U-boat code 1942 totals: 1383 merchant ships sunk 87 U-boats sunk

Feb – War changes in favor of the Allies March – Germany temporarily blocking code breaking 1943 totals: 588 merchant ships sunk 242 U-boats sunk

June 4th – D-Day Landing Aug. – Largest convoy arrives in U.K. with no losses 1944 totals: 251 merchant ships sunk 252 U-boats sunk

May 6th – Last U-boat sunk May 8th – Germany surrenders Sept. 2nd – Japan surrenders 1945 totals: 175 merchant ships sunk 120 U-boats sunk

U-Boats scuttled at the end of the war May 6-9, 1945: over 200 U-boats scuttled (sunk) by the Germans 156 U-boats were surrendered to the British Royal Navy 116 were scuttled by the U.K. off of Ireland May 06 to 09 1945 Over 200 U-boats were scuttled by the Germans Some U-boats were scuttled by the Germans by filling ballast tanks and not flooding the interior of the boat. During OPERATION DEADLIGHT 115 surrendered U-boats were scuttled North of Ireland. 42 surrendered U-boats Northern Ireland in June 1945

Essential Questions: What were the key elements of the Battle of the Atlantic? What things gave the Allies the advantage to win control over the Atlantic Ocean?