HMS Caradoc was a C-class light cruiser built for the Royal Navy during World War I. She was one of the four ships of the Caledon sub-class. Assigned to the Grand Fleet during the war, the ship participated in the Second Battle of Heligoland Bight in late 1917. Caradoc was briefly deployed to the Baltic in late 1918 supporting anti-Bolshevik forces during the British campaign in the Baltic and then was transferred to the Mediterranean Fleet in early 1919 and spent the next year and a half doing the same thing in the Black Sea during the Russian Civil War. The ship was withdrawn from the Black Sea in mid-1920 to observe the Greco-Turkish War of 1919–22 and the Chanak Crisis of late 1922. Caradoc spent most of the rest of her time between the World Wars overseas or in reserve with deployments to the Far East and the North America and West Indies Station.

HMS Cardiff was a C-class light cruiser built for the Royal Navy during World War I. She was one of the five ships of the Ceres sub-class and spent most of her career as a flagship. Assigned to the Grand Fleet during the war, the ship participated in the Second Battle of Heligoland Bight in late 1917. Cardiff was briefly deployed to the Baltic in late 1918 supporting anti-Bolshevik forces during the British campaign in the Baltic during the Russian Civil War.