The Great War
.303-inch Gun
During the Great War, the Royal Navy were the service that retained the Maxim machine gun for the longest period.
The Vickers would have been used with the Royal Marines as well as the Royal Naval Air Service. Their aircraft were equipped with Mk I* guns.

The Royal Naval Air Service were also equipped with armoured cars and these used the Maxim and the Vickers as their armament.
Inter-War Period
.303-inch Gun
The Fleet Air Arm, established in 1924, used aircraft equipped with the Mk II and subsequent variants of aircraft guns.
The Royal Marines continued to use the Vickers Mk I in the ground role.
.303-inch Gas Operated
For aircraft observers, the Vickers Gas-Operated No 1 Mk I was used on Fleet Air Arm aircraft. It was also used in an anti-aircraft role on submarines, being employed when the submarine was surfaced.
.5-inch
The main user of the Mk III .5-inch gun was the Royal Navy in multiple anti-aircraft mountings.
Second World War
The roles of the Vickers developed during the inter-war period remained during the Second World War.
Post-Second World War
The Royal Navy used the Vickers Gas-Operated guns in a limited role after the Second World War.