Fish was the quarry of H.M. trawler Imperialist before the war; now she hunts U-boats. Since early 1940, when she discarded fishing nets for guns and depth charges, the Imperialist has gained for herself a long record of achievements; she is credited with having shot down a German Condor aircraft which attempted to attack an Atlantic convoy, and with assisting at the capture of an enemy blockade runner. Her latest exploit, announced on Feb. 20, 1944, was a great part played in destroying a U-boat in the Straits of Gibraltar.
Describing this successful attack, the Commanding Officer of the Imperialist, Lieut.-Cmdr. B. H. Craig Rodgers, R.N.V.R., said: "The first salve from our 4-in. gun crippled the enemy's forward gun. The Imperialist's smaller armament must have scored nearly a hundred hits. The U-boat submerged or sank, so we proceeded over the position and dropped some more depth charges – about four tons in all."
Built in 1939, and in peacetime sailing from Hull, she began her fighting career in the early days of the Norwegian campaign.