HMS Anchusa (K186)

The Flower-class corvette was a British class of 294 corvettes used during World War II by the Allied navies particularly as anti-submarine convoy escorts in the Battle of the Atlantic. Royal Navy ships of this class were named after flowers.

A corvette is a small warship. It is traditionally the smallest class of vessel considered to be a proper warship. The warship class above the corvette is that of the frigate, while the class below was historically that of the sloop-of-war.

The Royal Navy (RN) is the United Kingdom's naval warfare force. Although warships were used by English and Scottish kings from the early medieval period, the first major maritime engagements were fought in the Hundred Years' War against France. The modern Royal Navy traces its origins to the early 16th century; the oldest of the UK's armed services, it is consequently known as the Senior Service.

Ceremonial ship launching involves the performance of ceremonies associated with the process of transferring a vessel to the water. It is a nautical tradition in many cultures, dating back thousands of years, to accompany the physical process with ceremonies which have been observed as public celebration and a solemn blessing, usually but not always, in association with the launch itself.

Belfast is the capital and largest city of Northern Ireland, standing on the banks of the River Lagan on the east coast. It is the 12th-largest city in the United Kingdom and the second-largest in Ireland. It had a population of 345,418 in 2021.

Northern Ireland is a part of the United Kingdom, situated in the north-east of the island of Ireland, that is variously described as a country, province or region. Northern Ireland shares an open border to the south and west with the Republic of Ireland. In 2021, its population was 1,903,100, making up about 27% of Ireland's population and about 3% of the UK's population. The Northern Ireland Assembly, established by the Northern Ireland Act 1998, holds responsibility for a range of devolved policy matters, while other areas are reserved for the UK Government. The government of Northern Ireland cooperates with the government of the Republic of Ireland in several areas agreed under the terms of the Belfast Agreement. The Republic of Ireland also has a consultative role on non-devolved governmental matters through the British-Irish Governmental Conference (BIIG).

The Hedgehog was a forward-throwing anti-submarine weapon that was used primarily during the Second World War. The device, which was developed by the Royal Navy, fired up to 24 spigot mortars ahead of a ship when attacking a U-boat. It was deployed on convoy escort warships such as destroyers and corvettes to supplement the depth charges.

A depth charge is an anti-submarine warfare (ASW) weapon. It is intended to destroy a submarine by being dropped into the water nearby and detonating, subjecting the target to a powerful and destructive hydraulic shock. Most depth charges use high explosive charges and a fuze set to detonate the charge, typically at a specific depth. Depth charges can be dropped by ships, patrol aircraft, and helicopters.

A submarine 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.

Nazi Germany was the German state between 1933 and 1945, when Adolf Hitler and the Nazi Party controlled the country, transforming it into a dictatorship. Under Hitler's rule, Germany quickly became a totalitarian state where nearly all aspects of life were controlled by the government. The Third Reich, meaning "Third Realm" or "Third Empire", alluded to the Nazi claim that Nazi Germany was the successor to the earlier Holy Roman Empire (800–1806) and German Empire (1871–1918). The Third Reich, which Hitler and the Nazis referred to as the Thousand-Year Reich, ended in May 1945 after just 12 years when the Allies defeated Germany, ending World War II in Europe.

U-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 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 to the Soviet Union and the Allied territories in the Mediterranean. German submarines also targeted Brazilian merchant ships during both World Wars and, twice over, precipitated Brazil's decision to give up its neutral stance and declare war on Germany.

Mauritius, officially the Republic of Mauritius, is an island nation in the Indian Ocean about 2,000 kilometres off the southeast coast of the African continent, east of Madagascar. It includes the main island, as well as Rodrigues, Agaléga and St. Brandon. The islands of Mauritius and Rodrigues, along with nearby Réunion, are part of the Mascarene Islands. The main island of Mauritius, where most of the population is concentrated, hosts the capital and largest city, Port Louis. The country spans 2,040 square kilometres (790 sq mi) and has an exclusive economic zone covering 2,300,000 square kilometres.