HMS Vanguard was one of three St Vincent-class dreadnought battleships built for the Royal Navy in the first decade of the 20th century. She spent her career assigned to the Home and Grand Fleets. Aside from participating in the Battle of Jutland in May 1916 and the inconclusive action of 19 August several months later, her service during World War I mostly consisted of routine patrols and training in the North Sea.