Admiral Sir John Jellicoe

John Jellicoe commanded the British Grand Fleet at the Battle of Jutland in 1916, the only full-scale clash of dreadnought battle fleets in the war. Winston Churchill later remarked that Jellicoe was 'the only man on either side who could have lost the war in an afternoon' -- reflecting the enormous strategic weight of preserving British naval supremacy, which the cautious, tactically inconclusive battle ultimately did.

Related

MyHistorian
A causal knowledge graph of history