Q-ships, also known as Q-boats, decoy vessels, special service ships, or mystery ships, were heavily armed merchant ships with concealed weaponry, designed to lure submarines into making surface attacks. This gave Q-ships the chance to open fire and sink them. The use of Q-ships contributed to the abandonment of cruiser rules restricting attacks on unarmed merchant ships and to the shift to unrestricted submarine warfare in the 20th century.
HMS Cleopatra (F28) was a Leander-class frigate of the Royal Navy (RN). Cleopatra was built at HMNB Devonport. She was launched on 21 March 1964, commissioned on 1 March 1966 and decommissioned on 31 January 1992.
A British submarine flotilla operated in the Baltic Sea for three years during the First World War. The squadron of nine submarines was attached to the Russian Baltic Fleet. The main task of the flotilla was to prevent the import of iron ore from Sweden to Imperial Germany. The success of the flotilla also forced the German Navy in the Baltic to keep to their bases and denied the German High Seas Fleet a training ground. The flotilla was based in Reval (Tallinn), and for most of its career commanded by Captain Francis Cromie.
HMS C3 was one of 38 C-class submarines built for the Royal Navy in the first decade of the 20th century. The boat was used to demolish a viaduct during the Zeebrugge Raid in 1918.
HMS C12 was one of 38 C-class submarines built for the Royal Navy in the first decade of the 20th century. The boat survived the First World War and was sold for scrap in 1920.
HMS C24 was one of 38 C-class submarines built for the Royal Navy in the first decade of the 20th century. The boat survived the First World War and was sold for scrap in 1921.
HMS C26 was one of 38 C-class submarines built for the Royal Navy in the first decade of the 20th century.
HMS C35 was one of 38 C-class submarines built for the Royal Navy in the first decade of the 20th century.
HMS C27 was one of 38 C-class submarines built for the Royal Navy in the first decade of the 20th century.
HMS C29 was one of 38 C-class submarines built for the Royal Navy in the first decade of the 20th century.
HMS C32 was one of 38 C-class submarines built for the Royal Navy in the first decade of the 20th century. The boat ran aground in the Baltic in 1917 and had to be destroyed to prevent her capture.
HMS C33 was one of 38 C-class submarines built for the Royal Navy in the first decade of the 20th century. The boat sank with all hands on 4 August 1915 after hitting a mine.
HMS Sterlet was a second-batch S-class submarine built during the 1930s for the Royal Navy. Completed in 1938, the boat fought in the Second World War. The submarine is one of the 12 boats named in the song Twelve Little S-Boats. Thus far she has been the only ship of the Royal Navy to be named Sterlet.
HMS Shark was a second-batch S-class submarine built during the 1930s for the Royal Navy. Completed in 1934, the boat fought in the Second World War. Shark is one of twelve boats named in the song "Twelve Little S-Boats".
HMS Snapper was a second-batch S-class submarine built during the 1930s for the Royal Navy. Completed in 1935, the boat participated in the Second World War. Snapper is one of the 12 boats named in the song "Twelve Little S-Boats".
HMS L23 was a L-class submarine built for the Royal Navy during World War I. The boat was not completed before the end of the war and was one of three L-class boats to serve during World War II. L23 was sold for scrap in 1946.
HMS L21 was a L-class submarine built for the Royal Navy during World War I. The boat was not completed before the end of the war and was sold for scrap in 1939.
The British campaign in the Baltic 1918–1919 was a part of the Allied intervention in the Russian Civil War. The codename of the Royal Navy campaign was Operation Red Trek. The intervention played a key role in enabling the establishment of the independent states of Estonia and Latvia. It failed to secure the control of Petrograd by White Russian forces, which was one of the main goals of the campaign.
The Atlantic U-boat campaign of World War I was the prolonged naval conflict between German submarines and the Allied navies in Atlantic waters—the seas around the British Isles, the North Sea and the coast of France.
HMS Vanessa (D29) was a V-class destroyer of the British Royal Navy that was in service during World War I and World War II.
Royal Navy 