Anti-submarine warfareAnti-submarine warfare (ASW, or in the older form A/S) is a branch of underwater warfare that uses surface warships, aircraft, submarines, or other platforms, to find, track, and deter, damage, or destroy enemy submarines. Such operations are typically carried out to protect friendly shipping and coastal facilities from submarine attacks and to overcome blockades. Successful ASW operations typically involved a combination of sensor and weapon technologies, along with effective deployment strategies and sufficiently trained personnel.
Battle of FranceThe Battle of France (bataille de France; 10 May – 25 June 1940), also known as the Western Campaign (German: Westfeldzug), the French Campaign (Frankreichfeldzug, campagne de France) and the Fall of France, was the German invasion of France during the Second World War. France and the Low Countries were conquered, ending land operations on the Western Front until the Normandy landings on 6 June 1944. On 3 September 1939, France declared war on Germany following the German invasion of Poland.
Adolf HitlerAdolf Hitler (ˈaːdɔlf ˈhɪtlɐ; 20 April 1889 - 30 April 1945) was an Austrian-born German politician who was the dictator of Germany from 1933 until his suicide in 1945. He rose to power as the leader of the Nazi Party, becoming the chancellor in 1933 and then taking the title of Führer und Reichskanzler in 1934. During his dictatorship, he initiated World War II in Europe by invading Poland on 1 September 1939. He was closely involved in military operations throughout the war and was central to the perpetration of the Holocaust, the genocide of about six million Jews and millions of other victims.
Signals intelligenceSignals intelligence (SIGINT) is intelligence-gathering by interception of signals, whether communications between people (communications intelligence—abbreviated to COMINT) or from electronic signals not directly used in communication (electronic intelligence—abbreviated to ELINT). Signals intelligence is a subset of intelligence collection management. As classified and sensitive information is usually encrypted, signals intelligence in turn involves the use of cryptanalysis to decipher the messages.
Norwegian campaignThe Norwegian campaign (8 April - 10 June 1940) involved the attempt by Allied forces to defend northern Norway coupled with the resistance of the Norwegian military to the country's invasion by Nazi Germany in World War II. Planned as Operation Wilfred and Plan R 4, while the German attack was feared but had not yet happened, the battlecruiser set out from Scapa Flow for the Vestfjorden with twelve destroyers on 4 April. The Royal Navy and the Kriegsmarine met at the First Battle of Narvik on 9 and 10 April, and British forces conducted the Åndalsnes landings on 13 April.
U-boatU-boats were naval submarines operated by Germany, particularly in the First and Second World Wars. Although at times they were efficient fleet weapons against enemy naval warships, they were most effectively used in an economic-warfare role (commerce raiding) and enforcing a naval blockade against enemy shipping. The primary targets of the U-boat campaigns in both wars were the merchant convoys bringing supplies from Canada and other parts of the British Empire, and from the United States, to the United Kingdom and (during the Second World War) to the Soviet Union and the Allied territories in the Mediterranean.
Escort carrierThe escort carrier or escort aircraft carrier (U.S. hull classification symbol CVE), also called a "jeep carrier" or "baby flattop" in the United States Navy (USN) or "Woolworth Carrier" by the Royal Navy, was a small and slow type of aircraft carrier used by the Royal Navy, the United States Navy, the Imperial Japanese Navy and Imperial Japanese Army Air Force in World War II. They were typically half the length and a third the displacement of larger fleet carriers, slower, more-lightly armed and armored, and carried fewer planes.
French NavyThe French Navy (Marine nationale), informally La Royale, is the maritime arm of the French Armed Forces and one of the four military service branches of France. It is among the largest and most powerful naval forces in the world, ranking seventh in combined fleet tonnage and fifth in number of naval vessels. The French Navy is one of eight naval forces currently operating fixed-wing aircraft carriers, with its flagship being the only nuclear-powered aircraft carrier outside the United States Navy, and one of two non-American vessels to use catapults to launch aircraft.
French ResistanceThe French Resistance (La Résistance) was a collection of organizations that fought the Nazi occupation of France and the collaborationist Vichy régime in France during the Second World War. Resistance cells were small groups of armed men and women (called the Maquis in rural areas) who conducted guerrilla warfare and published underground newspapers. They also provided first-hand intelligence information, and escape networks that helped Allied soldiers and airmen trapped behind Axis enemy lines.
SubmarineA submarine (or sub) is a watercraft capable of independent operation underwater. It differs from a submersible, which has more limited underwater capability. The term is also sometimes used historically or colloquially to refer to remotely operated vehicles and robots, as well as medium-sized or smaller vessels, such as the midget submarine and the wet sub. Submarines are referred to as boats rather than ships irrespective of their size.
Bletchley ParkBletchley Park is an English country house and estate in Bletchley, Milton Keynes (Buckinghamshire) that became the principal centre of Allied code-breaking during the Second World War. The mansion was constructed during the years following 1883 for the financier and politician Sir Herbert Leon in the Victorian Gothic, Tudor, and Dutch Baroque styles, on the site of older buildings of the same name. During World War II, the estate housed the Government Code and Cypher School (GC&CS), which regularly penetrated the secret communications of the Axis Powers - most importantly the German Enigma and Lorenz ciphers.