HMS Camellia (K31)

A merchant ship, merchant vessel, trading vessel, or merchantman is a watercraft that transports cargo or carries passengers for hire. This is in contrast to pleasure craft, which are used for personal recreation, and naval ships, which are used for military purposes.

In naval terminology, a destroyer is a fast, manoeuvrable, long-endurance warship intended to escort larger vessels in a fleet, convoy, or battle group and defend them against powerful short-range attackers. They were originally developed in 1885 by Fernando Villaamil for the Spanish Navy as a defense against torpedo boats, and by the time of the Russo-Japanese War in 1904, these "torpedo boat destroyers" (TBDs) were "large, swift, and powerfully armed torpedo boats designed to destroy other torpedo boats". Although the term "destroyer" had been used interchangeably with "TBD" and "torpedo boat destroyer" by navies since 1892, the term "torpedo boat destroyer" had been generally shortened to simply "destroyer" by nearly all navies by the First World War.

HMS Harvester was an H-class destroyer originally ordered by the Brazilian Navy with the name Jurua in the late 1930s, but bought by the Royal Navy after the beginning of World War II in September 1939. Almost immediately after being commissioned, in May 1940, the ship began evacuating Allied troops from Dunkirk and other locations in France. Afterwards she was assigned to the Western Approaches Command for convoy escort duties. Harvester and another destroyer sank a German submarine in October. She was briefly assigned to Force H in May 1941, but her anti-aircraft armament was deemed too weak and she was transferred to the Newfoundland Escort Force in June 1941 for escort duties in the North Atlantic. The ship was returned to the Western Approaches Command in October 1941 and was converted to an escort destroyer in early 1942. Harvester was torpedoed and sunk in March 1943 by a German submarine after having rammed and sunk another submarine the previous day while escorting Convoy HX 228.

German submarine U-107 was a Type IXB U-boat of Nazi Germany's Kriegsmarine that operated during World War II. Between January 1941 and August 1944, she sailed on 13 active patrols at a time when a U-boat averaged a lifespan of seven to ten patrols. During that time, U-107 sank 39 Allied ships and damaged four. The U-boat was launched on 2 July 1940, based at the U-boat port of Lorient, with a crew of 53 under the initial command of Günter Hessler. She was later commanded, in order, by Harald Gelhaus, Valker Simmermacher and her final commander, Karl Heinz Fritz.

A convoy is a group of vehicles, typically motor vehicles or ships, traveling together for mutual support and protection. Often, a convoy is organized with armed defensive support and can help maintain cohesion within a unit. It may also be used in a non-military sense, for example when driving through remote areas.

Iceland is a Nordic island country in the North Atlantic Ocean and in the Arctic Ocean. Iceland is the most sparsely populated country in Europe. Iceland's capital and largest city is Reykjavík, which is home to about 36% of the population. Iceland is the largest part of the Mid-Atlantic Ridge that rises above sea level, and its central volcanic plateau is erupting almost constantly. The interior consists of a plateau characterised by sand and lava fields, mountains, and glaciers, and many glacial rivers flow to the sea through the lowlands. Iceland is warmed by the Gulf Stream and has a temperate climate, despite a high latitude just outside the Arctic Circle. Its high latitude and marine influence keep summers chilly, and most of its islands have a polar climate.

A sister ship is a ship of the same class or of virtually identical design to another ship. Such vessels share a nearly identical hull and superstructure layout, similar size, and roughly comparable features and equipment. They often share a common naming theme, either being named after the same type of thing or person or with some kind of alliteration. Typically the ship class is named for the first ship of that class. Often, sisters become more differentiated during their service as their equipment are separately altered.

HMS Arbutus was a Flower-class corvette of the Royal Navy, which was active during the Second World War. She was a successful escort vessel, and took part in the destruction of two U-boats during the Battle of the Atlantic. Arbutus was sunk in the North Atlantic in February 1942.