Launched on 30 December 1915, the vessel fought in the Battle of Jutland between 31 May and 1 June 1916 and subsequently served in anti-submarine and escort duties based at Cobh in Ireland.

The remit was to have a maximum speed of 36 knots (67 km/h; 41 mph) and, although the eventual design did not achieve this, the greater performance was appreciated by the navy.

A fuel load of 296 long tons (301 t) of oil was carried, giving a design range of 3,450 nautical miles (6,390 km; 3,970 mi) at 15 kn (28 km/h; 17 mph).

[5] Narwhal was laid down by William Denny and Brothers of Dumbarton on 21 April 1915 with the yard number 1046, launched on 30 December and completed on 3 March the following year.

[10] In February 1917, the destroyer was transferred to Cobh, Ireland, to counter increasing activity by German submarines in the Southwest Approaches.

[16] After the Armistice of 11 November 1918 that ended the war, the destroyer remained in Devonport and, shortly afterwards, joined the local defence flotilla at the base.