In 1900 the Royal Navy ordered five submarines from Vickers Shipbuilding and Engineering of Barrow-in-Furness, designed by Electric Boat Company.

En route to a training exercise with the fleet in a disaster, afterwards nicknamed "the battle of May Island", two K-class submarines were sunk, with death of most of their crew, and three more and a light cruiser damaged.

[6] In the Mediterranean (during the Siege of Malta), British U-class submarines began operations against Italy as early as January 1941.

Owing to the shortage of torpedoes, enemy ships could not be attacked unless the target in question was a warship, tanker or other "significant vessel".

He received the Victoria Cross for attacking a well-defended convoy on 25 May 1941 and sinking an Italian liner, the Conte Rosso.

The Resolution class ballistic missile submarines (SSBNs) were introduced to carry out this role under the Polaris programme from 1968.

[13] HMS Conqueror made history in 1982 during the Falklands War when she became the first nuclear-powered submarine to sink a surface ship, the General Belgrano.

[14] In 1999 Splendid participated in the Kosovo Conflict and became the first Royal Navy submarine to fire a Tomahawk cruise missile in anger.

[19] In April 2016, The Sunday Times reported that Royal Navy submarines were to resume under-ice operations in the Arctic.

The crews of all seven active Royal Navy attack submarines will receive training on how to navigate below and "punch through" ice floes.

[20] As of 2018, there had been three near misses between submerged Royal Navy submarines and civilian vessels due to "an insufficient appreciation of the location of surface ships in the vicinity", according to a Marine Accident Investigation Branch report.

[21] For an extended period of time, the navy has had difficulty in attracting specialist staff into the nuclear submarine force, in part because of the long undersea patrols.

A failure on Perisher means that the unsuccessful candidate is not permitted to return to sea as a member of the Submarine Service (although they are still allowed to wear the dolphin badge).

These include slang unique to submariners (such as referring to the torpedo storage compartment as the Bomb Shop and the diesel engine room as the Donk Shop[27]), a special communications code known as the Dolphin Code and the entitlement of a sailor to wear Dolphins and black cap covers upon entering the service.

Rear-Admiral Arthur Wilson VC, the Controller of the Royal Navy, has gone down in history as the officer who claimed in 1901 "[Submarines are] underhand, unfair, and damned un-English.

[29] The legend goes that in response to these top secret remarks of Wilson's made 13 years earlier Lieutenant-Commander (later Admiral Sir) Max Horton first flew the Jolly Roger on return to port after sinking the German cruiser Hela and the destroyer S-116 in 1914 while in command of the E-class submarine E9.

[30] In World War II it became common practice for the submarines of the Royal Navy to fly the Jolly Roger on completion of a successful combat mission where some action had taken place, but as an indicator of bravado and stealth rather than of lawlessness.

For example, in 1982 returning from the Falklands conflict Conqueror flew the Jolly Roger depicting one dagger for the SBS deployment to South Georgia and one torpedo for her sinking of the Argentinian cruiser General Belgrano.

[31] First officially adopted in the 1950s, qualified submariners are presented the Golden Dolphins badge to wear on their uniform on the left breast above any medals.

[32] The current badge, adopted in 1972, depicts two golden dolphins facing an anchor surmounted by St Edwards Crown.

The four Vanguard class boats are responsible for the United Kingdom's nuclear deterrent, and use the Trident missile system.

[40] The National Audit Office in 2019 stated that the accumulative costs of laid up storage had reached £500 million,[41] and they represent a liability of £7.5 billion.

Boat number seven was confirmed in the October 2010 Strategic Defence and Security Review and long-lead items have been ordered.

The submarine's armament consists of up to 38 Spearfish torpedoes and Tomahawk Block IV land-attack cruise missiles.

[48] However, in 2023 the program expanded to include the joint acquisition, with American support, of nuclear-powered submarines by the United Kingdom and Australia.