World War II
Battle of the Atlantic
During World War II both the Allies and the Axis Powers fought for control of the Atlantic Ocean. The Allies wanted to use the Atlantic to resupply Great Britain and the Soviet Union in their fight against Germany and Italy. The Axis Powers wanted to stop them. This fight for control of the Atlantic Ocean is called the Battle of the Atlantic.
A U-boat shells a merchant ship
Source: United Kingdom Government
Where did it take place?
The Battle of the Atlantic took place throughout the northern region of the Atlantic Ocean. Once the United States entered the war the battle spread all the way to the coast the United States and the Caribbean Sea.
How long did it last?
The battle lasted over 5 years and 8 months from September 3, 1939 to May 8, 1945.
The early battles in the Atlantic heavily favored the Germans. They used their submarines to sneak up on British ships and sink them with torpedoes. The Allies didn't know what to do and lost a lot of ships over the first few years of the war.
German submarines were called U-boats. This was short for "Unterseeboot", which meant "undersea boat." The Germans quickly ramped up manufacture of their U-boats and had hundreds of submarines patrolling the Atlantic Ocean by 1943.
A German U-boat Surfacing
Source: United Kingdom Government
The Allies tried to counter the U-boat attacks by travelling in large groups called convoys. They often had destroyer warships that would help to escort them and defend them from attacks. For a period of time in 1941 this method was fairly effective in helping get many ships through safely to Britain. However, as the Germans built more and more submarines the convoys became less successful.
A Convoy Crossing the Atlantic
Source: U.S. Navy Naval History Center
Secret Codes and Innovations
In 1943 the battle reached its peak. The Germans had a large number of submarines in the Atlantic, but the Allies had broken the German secret codes and had developed new technologies for fighting submarines. The Allies used radar to tell where the ships were and special new underwater bombs called Hedgehogs that helped to destroy the submarines.
The Battle Turns in Favor of the Allies
By the middle of 1943, the battle had turned in favor of the Allies. From this point on in the war, the United States was able to more freely ship supplies to Great Britain including the large supply of soldiers and weapons needed for the Normandy Invasion.
The control of the Atlantic had a major impact on the outcome of the war. Keeping Britain supplied helped to keep the Germans from taking over all of Western Europe.
The losses in the battle were staggering. Over 30,000 sailors were killed on each side. The Allies lost around 3,500 supply ships and 175 warships. The Germans lost 783 submarines.
Interesting Facts about the Battle of the Atlantic
- Winston Churchill first called it the "Battle of the Atlantic" in 1941.
- It was estimated that at least 20 supply ships needed to arrive each day in Britain in order for them to continue to fight the war.
- The Allies lost 1,664 supply ships in 1942.
- The Germans sometimes used a "wolf pack" tactic where a number of submarines would surround and attack a supply convoy at once.
- Allied planes used a large spotlight called the Leigh Light to spot submarines that had surfaced at night.
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