Rear Admiral Sir Robert Keith Arbuthnot, 4th Baronet, was a Royal Navy officer during the First World War. He was killed at the Battle of Jutland, when the cruiser squadron he commanded came under heavy fire after a bold but ill-judged attack on the German battle fleet.

The Battle of Jutland was a naval battle between Britain's Royal Navy Grand Fleet, under Admiral Sir John Jellicoe, and the Imperial German Navy's High Seas Fleet, under Vice-Admiral Reinhard Scheer, during World War I. The battle unfolded in extensive manoeuvring and three main engagements from 31 May to 1 June 1916, off the North Sea coast of Denmark's Jutland Peninsula. It was the largest naval battle and only full-scale clash of battleships of the war, and the outcome ensured that the Royal Navy denied the German surface fleet access to the North Sea and the Atlantic for the remainder of the war, as Germany avoided all fleet-to-fleet contact thereafter. Jutland was also the last major naval battle, in any war, fought primarily by battleships.