In 1911, Colonel Isaac N. Lewis, U.S.Army, developed a gas-operated light machine gun which, when built for the Belgian Army, soon attracted the attention of the British War Office who at the start of The Great War (1914) were eagerly seeking a more mobile machine gun than the heavy Vickers-Maxim. Quicker and cheaper to be built than the Vickers-Maxim (six could be turned out for the same manufacturing effort as one Vickers) a license was soon obtained to build the Lewis-Gun at the Birmingham Small Arms Company's factory in Warwickshire.
Throughout the Great War the Lewis Gun, issued to Battalions of the expanding BEF, introduced a new concept in Machine Gun use. It was ideal for use in the trenches where, despite being susceptible to dirt and mud, it could be easily concealed, as well as having the ability to be operated by just one man. By 1918 each infantry squad had a Lewis, which substantially increased the battalion's firepower and made the British infantry far more formidable than the Germans, who had no comparable gun.
The Lewis-Gun did have its faults. It was rather notorious for stoppages and jams, and the circular 47-round magazine which took time to reload was another general well-known barrack-room moan. Nevertheless the troops had confidence in it, which was what mattered most.
The Lewis also performed well as an aircraft armament (with a 97-round ammunition pan) and was one of the few machine guns that could be used for shooting forward by the pilot or, on a flexible mounting, by the rear Observer.
Surviving the Great War, the Lewis MG continued in infantry service until 1939 when it was finally replaced by the newer Bren LMG. However the threat of German invasion in the Summer of 1940 would bring about the hasty reintroduction from store of some 50,000 Lewis guns, mainly to equip the Home Guard and the Merchantile Marine Service. Thus the useful Lewis would once again provide good service for the many years of conflict to follow.