Glowworm was transferred from the Mediterranean Fleet shortly after the beginning of Second World War to the British Isles, to escort shipping in local waters.

On 8 April 1940 Glowworm encountered German destroyers transporting troops to invade Norway in Operation Weserübung.

In the battle, Glowworm, severely damaged, rammed Admiral Hipper, losing its bow and sinking shortly afterwards.

Glowworm carried a maximum of 470 long tons (480 t) of fuel oil that gave her a range of 5,530 nautical miles (10,240 km; 6,360 mi) at 15 knots (28 km/h; 17 mph).

[2] Glowworm was ordered from the yards of John I. Thornycroft and Company, at Woolston, Hampshire on 5 March 1934 under the 1933 Construction Programme.

Between 10 August and 9 September 1936, together with Grafton, she escorted the yacht Nahlin as King Edward VIII cruised the eastern Mediterranean.

Glowworm returned to Portsmouth for a longer overhaul between 7 June and 25 July 1938 and escorted the ocean liner SS Strathnaver between Malta and Alexandria during the Munich Crisis in September 1938.

Glowworm suffered significant structural damage and was under repair at a commercial dockyard in Hull until late March.

[8] On the morning of 8 April 1940 Glowworm was on her way to rejoin Renown when she encountered the German destroyers Z11 Bernd von Arnim and Z18 Hans Lüdemann in the thick fog before 8:00 a.m.

Hipper had difficulty in distinguishing Glowworm from von Arnim but opened fire eight minutes later at a range of 8,400 m (27,600 ft) with the 20.3-centimetre (8.0 in) main armament.

The two ships were very close when Hipper emerged from the smoke and Roope ordered a hard turn to starboard to ram the cruiser.

The senior surviving officer, Lieutenant Ramsay, told his rescuers that neither the helm nor the emergency steering was manned when the ships collided.

[14] The award was justified, in part, by the recommendation of Heye, who wrote to the British authorities via the Red Cross, stating the dauntless courage Roope had shown when engaging a much superior ship at short range.