Battle of the Atlantic in the context of "World War II"

Ascension Island is an isolated volcanic island, 7°56′ south of the Equator in the South Atlantic Ocean. It is about 960 miles (1,540 km) from the coast of Africa and 1,400 miles (2,300 km) from the coast of South America. It is governed as part of the British Overseas Territory of Saint Helena, Ascension and Tristan da Cunha, of which the main island, Saint Helena, is around 800 miles (1,300 km) to the southeast. The territory also includes the sparsely populated Tristan da Cunha archipelago, 2,000 miles (3,200 km) to the south, about halfway to the Antarctic Circle.

Ascension Island was possibly discovered by the Portuguese seafarer João da Nova in 1501, before being named Ascension by Afonso de Albuquerque in 1503 on Ascension Day. Ascension Island was garrisoned by the British Admiralty from 22 October 1815 to 1922 and was an important refuelling stop for ships and commercial airliners in the days of international air travel by flying boats. During World War II, it was an important naval and air station, especially providing antisubmarine warfare bases in the Battle of the Atlantic.

Japan's attack on Pearl Harbor took place on December 7, 1941. The United States military suffered 19 ships damaged or sunk, and 2,403 people were killed. Its most significant consequence was the entrance of the United States into World War II. The US had previously been officially neutral and considered an isolationist country with its Neutrality Act but subsequently after the attack declared war on Japan the next day and entered the Pacific War. Then on December 11, 1941, four days after the Japanese attack, after the Italian declaration of war on the United States and the German declaration of war against the United States, which Hitler had orchestrated, the US was then at war with Germany and Italy. The US then became involved in the Battle of the Atlantic and the European theatre of war as well as with Japan.

Following the attack, the US interned 120,000 Japanese Americans, 11,000 German Americans, and 3,000 Italian Americans.

A battle is an occurrence of combat in warfare between opposing military units of any number or size. A war usually consists of multiple battles. In general, a battle is a series of military engagements that is well defined in duration, area, and force commitment. An engagement with only limited commitment between the forces and without decisive results is sometimes called a skirmish.

The word "battle" can also be used infrequently to refer to an entire operational campaign, although this usage greatly diverges from its conventional or customary meaning. Generally, the word "battle" is used for such campaigns if referring to a protracted combat encounter in which either one or both of the combatants had the same methods, resources, and strategic objectives throughout the encounter. Some prominent examples of this would be the Battle of the Atlantic, Battle of Britain, and the Battle of France, all in World War II.

The military history of the United Kingdom in World War II covers the Second World War against the Axis powers, starting on 3 September 1939 with the declaration of war by the United Kingdom and France, followed by the UK's Dominions, Crown colonies and protectorates on Nazi Germany in response to the invasion of Poland by Germany. There was little, however, the Anglo-French alliance could do or did do to help Poland. The Phoney War culminated in April 1940 with the German invasion of Denmark and Norway. Winston Churchill became prime minister and head of a coalition government in May 1940. The defeat of other European countries followed – Belgium, the Netherlands, Luxembourg and France – alongside the British Expeditionary Force which led to the Dunkirk evacuation in June 1940.

Britain and its Empire continued the war against Germany. Churchill engaged industry, scientists and engineers to advise and support the government and the military in the prosecution of the war effort. Germany's planned invasion of the UK was averted by the Royal Air Force denying the Luftwaffe air superiority in the Battle of Britain, and by its marked inferiority in naval power. Subsequently, urban areas in Britain suffered heavy bombing during the Blitz in late 1940 and early 1941. The Royal Navy sought to blockade Germany and protect merchant ships in the Battle of the Atlantic. The Army counter-attacked in the Mediterranean and Middle East, including the North-African and East-African campaigns, and in the Balkans.

The Blockade of Germany (1939–1945), also known as the Economic War, involved operations carried out during World War II by the British Empire and by France in order to restrict the supplies of minerals, fuel, metals, food and textiles needed by Nazi Germany – and later by Fascist Italy – in order to sustain their war efforts. The economic war consisted mainly of a naval blockade, which formed part of the wider Battle of the Atlantic, but also included the bombing of economically important targets and the preclusive buying of war materials from neutral countries in order to prevent their sale to the Axis powers.

• The first period, from the beginning of European hostilities in September 1939 to the end of the "Phoney War", saw both the Allies and the Axis powers intercepting neutral merchant ships to seize deliveries en route to their respective enemies. Naval blockade at this time proved less than effective because the Axis could get crucial materials from the Soviet Union until June 1941, while Berlin used harbours in Spain to import war materials into Germany.
• The second period began after the rapid Axis occupation of the majority of the European landmass (Scandinavia, Benelux, France and the Balkans) in 1940–1941, resulting in Axis control of major centres of industry and agriculture.
• The third period started in December 1941 after the attack on Pearl Harbor by the Imperial Japanese Navy Air Service brought the U.S. officially into the European war.
• The final period came after the tide of war finally turned against the Axis after heavy military defeats up to and after D-Day in June 1944, which led to gradual Axis withdrawals from the occupied territories in the face of the overwhelming Allied military offensives.