The HMS Cossack (L03, F03, G03) was a Tribal class destroyer commissioned in the 1930s. She was laid down at the Walker Naval Yard of Vickers-Armstrongs in Newcastle upon Tyne on 9 June 1936, launched on 8 June 1937 by Mrs. S. V. Goodall, commissioned on 7 June 1938 and completed on 14 June 1938.
On September 12, 1939, the Cossack encountered a convoy of German merchant vessels escorted by destroyers in the Heligoland Bight. It was almost immediately noticed and attacked by Kriegsmarine forces, though it managed to last long enough to be saved by No. 1 Battlegroup