BL 4-inch Mk IX naval gun

HMS Repulse was one of two Renown-class battlecruisers built for the Royal Navy during the First World War. Originally laid down as an improved version of the Revenge-class battleship, her construction was suspended on the outbreak of war because she would not be ready in time. Admiral Lord Fisher, upon becoming First Sea Lord, gained approval for her to resume construction as a battlecruiser that could be built and enter service quickly. The Director of Naval Construction (DNC), Eustace Tennyson-d'Eyncourt, quickly produced an entirely new design to meet Admiral Lord Fisher's requirements and the builders agreed to deliver the ship in 15 months. They did not quite meet that ambitious goal, but the ship was delivered a few months after the Battle of Jutland in 1916. Repulse and her sister ship Renown, were the world's fastest capital ships upon completion.

The BL 4-inch Mark VIII naval gun was a British medium-velocity wire-wound naval gun introduced in 1908 as an anti-torpedo boat gun in smaller ships whose decks could not support the strain of the heavier and more powerful Mk VII gun.

The capital ships of a navy are its most important warships; they are generally the larger ships when compared to other warships in their respective fleet. A capital ship is generally a leading or a primary ship in a naval fleet.

Jane's Fighting Ships by Janes Information Services is an annual reference book of information on all the world's warships arranged by nation, including information on ships' names, dimensions, armaments, silhouettes and photographs, etc. Each edition describes and illustrates warships of different national naval and paramilitary forces, providing data on their characteristics. The first issue was illustrated with Jane's own ink sketches--photos began to appear with the third volume in 1900. The present title was adopted in 1905.

World War II or the Second World War, often abbreviated as WWII or WW2, was a global conflict that lasted from 1939 to 1945. The vast majority of the world's countries, including all of the great powers, fought as part of two opposing military alliances: the Allies and the Axis. Many participants threw their economic, industrial, and scientific capabilities behind this total war, blurring the distinction between civilian and military resources. Aircraft played a major role, enabling the strategic bombing of population centres and the delivery of the only two nuclear weapons ever used in war.

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.

A minesweeper is a small warship designed to remove or detonate naval mines. Using various mechanisms intended to counter the threat posed by naval mines, minesweepers keep waterways clear for safe shipping.

The QF 4-inch Mk XIX gun was a British low-velocity 4-inch 40-calibre naval gun used to arm small warships such as Bathurst and Castle-class corvette and some River-class frigate in World War II, mainly against submarines.

HMCS Sackville is a Flower-class corvette that served in the Royal Canadian Navy and later served as a civilian research vessel. She is now a museum ship located in Halifax, Nova Scotia, and the last surviving Flower-class corvette.

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.

Halifax is the capital and largest municipality of the Canadian province of Nova Scotia, and the largest municipality in Atlantic Canada. Halifax is one of Canada's fastest growing municipalities, and as of 2022, it is estimated that the CMA population of Halifax was 480,582, with 348,634 people in its urban area. The regional municipality consists of four former municipalities that were amalgamated in 1996: Halifax, Dartmouth, Bedford, and Halifax County.

Kingston upon Hull, usually abbreviated to Hull, is a port city and unitary authority in the East Riding of Yorkshire, England. It lies upon the River Hull at its confluence with the Humber Estuary, 25 miles (40 km) inland from the North Sea and 37 miles (60 km) south-east of York, the historic county town. With a population of 267,014 (2021), it is the fourth-largest city in the Yorkshire and the Humber region after Leeds, Sheffield and Bradford.