Frederick Coplestone was born on 12 September 1882, the son of Mr F Coplestone, CBE, JP and Mrs Coplestone of Barrel Well House, Chester. He joined the Royal Navy in 1898.

In 1904, as Sub Lieutenant, he was appointed to the Submarine Depot Ship HMS THAMES ‘for Training’ and, by December 1905, as a Lieutenant, he was appointed ‘for Command of Submarines’.

Frederick Coplestone was ‘invalided’ out of the Navy in 1906 having been deafened by gunfire. He volunteered for further service at the outbreak of war and was given the rank of Lieutenant Commander on the Emergency List and appointed to the Submarine Depot Ship HMS MAIDSTONE (8th Submarine Flotilla) ‘for Submarines’ and later appointed ‘for Submarine D2 – additional’. The Commodore (Submarines) – Roger Keyes – reported that Frederick Coplestone had almost begged for an opportunity to serve in a Submarine again.

On 24 November 1914 HMS D2 sailed for a patrol off the German Coast. The Submarine did not return and was deemed lost with all hands on 1 December 1914.

Frederick Coplestone is commemorated on the Portsmouth Naval War Memorial on Panel No. 1. There is also a commemorative stained glass window in Chester Cathedral, given by Frederick Coplestone’s widow, also commemorating  two other family members, including Commander A F Coplestone Boughey who was killed in the Battle of Jutland in 1916.